Hyundai Sonata Plug-in 2017 — Problemas relatados

On the morning of XXX, when starting my vehicle, I noticed that the oil warning light was flashing. The outside temperature was in the low 40s, which immediately raised concerns about the vehicle's engine and oil pressure. I promptly shut off the engine and checked the oil level. The oil level was full, as I expected, because I had checked it the previous day. I have consistently paid close attention to the oil level in this vehicle because it has consumed oil throughout the entire time I have owned it, beginning shortly after I purchased it brand new. Due to this ongoing issue, I make it a point to keep extra engine oil in my trunk so I can monitor and maintain the proper oil level. On XXXX, I stopped by the Joe Holland Hyundai Service Department and spoke with [XXX] about the oil warning light continuing to flicker while driving. Unfortunately, no resolution or explanation was provided. However, [XXX] did acknowledge that the engine in my vehicle had previously been identified on a problem list due to a machining error that occurred during the engine manufacturing process. This acknowledgment is particularly concerning because it suggests that Hyundai was aware of a potential manufacturing defect involving this engine. Despite the vehicle's ongoing oil consumption and the appearance of the oil warning light, I have yet to receive a satisfactory explanation or resolution from the dealership. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The contact owns a 2017 Hyundai Sonata. The contact stated that while driving at 65 MPH, there was an abnormal sound coming from the vehicle with the check engine warning light illuminated. The vehicle was taken to an independent mechanic, where it was diagnosed with engine failure. The contact was informed that the engine was consuming oil. The contact referenced an unknown recall; however, the VIN was not under recall. The contact was informed to take the vehicle to the dealer for assistance. The failure mileage was approximately 180,000.

The contact owns a 2017 Hyundai Sonata. The contact stated that while driving at 65 MPH, there was smoke coming from under the hood, and the vehicle lost automotive power and the vehicle was barely moving. The contact was able to drive the vehicle to the residence at a slow speed. The vehicle was taken to an independent mechanic, and the contact was informed that the engine was consuming an excessive amount of engine oil and that there was no oil in the engine. The contact stated that the vehicle had received an oil change one week prior to the failure. The dealer was contacted and made aware of the failure. The failure mileage was approximately 180,000.

I had recently taken my 2017 Hyundai Sonata in for an Engine Diagnostic check at the Bel Air Hyundai dealership, (10/15/26) worth $199.99 for an hour of maintenance, after experiencing sudden jolts when powering on and driving, needing additional time warming up. My initial thought was that the temperature gauge had gotten stuck again, or that the sensor needed to be fixed. I suggested that the dealership check for this issue before doing the diagnostic to see if it was still needed afterward. My service advisor, Kevin, said that this is included as part of the diagnostic testing. I figured it would be in the best interest for my vehicle to do an initial check, regardless of cost, to avoid further complications down the line, yet the 9 C2 update was performed without my consent or knowledge beforehand. They performed a multipoint inspection, which shows on record I had it done months prior during my last oil change, free of charge on both occasions, yet it only shows the vehicle, not engine. I have the lifetime warranty as advertised, covered by Zurich, which my service advisor showed me on his computer. However, he said my concern was a mechanical issue, not covered under this warranty. After the diagnostic was performed, I was shown the invoice, including the 9 C2 emissions page at the end, explaining the effects of this update. It does not serve as a systemic improvement, but a worsening change in operation and performance. I was only told about the service after it was performed. It is astounding because the side effects explained on the 9 C2 form are the actual concerns I had before bringing the car in. The update was not a necessary procedure, from my understanding this will only lead to more safety risks down the line. After doing research, given recent complaints about how it has affected many vehicles, I must share that they should have notified me beforehand to be aware about these risks so that I could make the personal decision for my vehicle.

I had my engine replaced under the Theta Engine lawsuit and I was due for the 9C2 service campaign and it was installed...ever since I picked up my car it shifts weird between 1st and 2nd. I brought it back to a different Hyundai dealer as the warranty work was done at another location and they recommended a transmission flush and relearn. They can feel it slipping and the other dealership noted no problems, which leads me to believe it was because of the service campaign. I also called corporate and the customer service rep had heard of this before as well as a bunch of forums online.

I am reporting an unaddressed, critical safety defect involving the Theta II engine in my 2017 Hyundai Sonata. The engine has developed a severe internal metallic knocking noise consistent with connecting rod bearing failure—the exact manufacturing defect associated with Hyundai's major engine recall campaigns (such as Recall 198 / Campaign 966)

I was driving down the road when my sunroof glass completely ripped away from the top and flew off. The glass is gone but the frame is still there but bent. I took it to a auto glass repair shop that stated "sunroof glass separated from urethane, came off and bent frame." I am dropping off at Hyundai dealership 9.17.26 to have them inspect. My insurance will not cover repairs. So I am hoping maybe this has happened to other people. There was a recall on sunroofs for the 2014-2016 Hyundai Sonata's NHTSA campaign 16V726000 A bonding issue with the front sunroof wind deflector anchor plate can cause the deflector to come loose and jam the glass panel when closing, or detach entirely while the car is moving.

The vehicle suffered a sudden, catastrophic internal mechanical engine failure out of nowhere without any warning lights or previous symptoms. An inspection of the engine cylinder revealed a physical hole blown through the top of the Cylinder 2 piston, causing immediate and complete loss of engine compression. This sudden structural failure caused the vehicle to completely lose all propulsion and stall unexpectedly while in operation, creating an immediate, severe safety hazard on the road.This vehicle features Hyundai's 2.4L Theta II Gasoline Direct Injection (GDI) engine, a family with a well-documented history of manufacturing defects, severe oil consumption, and catastrophic internal structural failures. Because this failure occurred instantly and without a progressive warning, it put occupants at risk of a severe rear-end collision or stranding in an unsafe traffic pattern. I am filing this safety report because the catastrophic destruction of the internal engine components presents a persistent and dangerous hazard to public safety.

We had a recall done, Campaign 92C, and every since then the car drives horrible. It's worse when cool, it sputters, and hesitates especially when excellerating. Even after warmed up it seems to slam in and out of gear at low speeds, even when foot is not on the gas. The drive is choppy. The dealership told us to drive it and let the transmission "learn" our driving patterns, but it has not resolved itself. Before campaign car ran smooth, now shuttering and sputtering.

I was driving and all of a sudden the traction lights turned on and the sterring wheel is hard to turn. Almost go in a car accident. The windows just stopped working and the brakes light constantly keep getting burned out.

I am writing to report a direct violation of the Theta II Class Action Settlement terms by Hyundai Motor America. This morning , I emailed an Executive Case Manager explicitly explaining that my 2017 Sonata has an active P1326 code, has the 2019 KSDS update, and requires a mandatory diagnostic under NHTSA Recall 17V226 that cannot be denied due to a salvage title. Instead of replying to my facts, the Case Manager Kathy gave me a hard denial falsely framing my federal recall safety request as a "voluntary goodwill warranty" issue to justify her rejection. Please help me in getting authorization my car with Hyundai dealership in Plano Tx to run the bearing rod test and get it fixed.

My engine seemed to be consuming oil way to much I had to do a oil change at 61,000 recommend by tire plus but at 58,000 is when I had to change my oil I also noticed there is a buring smell and its also been leaking oil at times I went to get it checked out by a mechanic at tireplus but they also they are seeing that the oil consumption was not normal and they recommend a possible recall for it because it hazardous for how fast its consuming and the leaks

Driving home from work on [XXX] (not a safe location)when my car lost power and engine light began to flash. I pulled off to the side of road and called my dad. He came with a code reader and said there was a code P1326. He cleared the code and car drove normally again. 2 days later it began to run rough. I was told about the engine recall so I called Hyundai corporate and told them this same story. I was advised to take to dealership and have the “rod bearings inspected” and shouldn’t matter that my dad cleared the code. The dealership(Massey Hyundai MD) said it had a burnt valve and not part of warranty. But never checked rod bearings. When I called corporate. They said nothing they could do. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

High oil consumption, burning a quart of oil or more every 500 miles since bought used at Hyundai dealership.

My 2017 Hyundai Sonata SE, equipped with the Theta II 2.4L GDI engine, is experiencing severe powertrain failures including rhythmic metallic engine knocking, catastrophic oil consumption, and un-commanded surges/jumping in speed while driving. These symptoms manifested following an unauthorized engine replacement performed by Hyundai of El Cajon under Repair Order [XXX], where the dealer covertly outsourced my vehicle to a third-party shop (Legacy Motor Works) to install an unverified used salvage engine block rather than a certified factory assembly. This vehicle is a Class Vehicle under In re: Hyundai and Kia Engine Litigation (Case No. [XXX]), and the KSDS software update (Campaign 953) was successfully completed on my vehicle in 2019. The engine knock, surging, and oil consumption are consistent with the known connecting rod bearing failure defect described in NHTSA investigation PE17-007. The dealership is currently denying warranty coverage, citing a mileage limit that does not exist under my Lifetime Powertrain Warranty, and they are withholding physical documentation of the repair terms. The vehicle is also experiencing secondary safety failures, including a continuous airbag SRS warning light (two years) and electrical shorts caused by the salvage-yard alternator installation, which have destroyed 4 to 5 car batteries. This engine failure represents a significant safety hazard, as the vehicle periodically loses power and surges without driver input. I am requesting that NHTSA investigate this pattern of warranty denial, parts-sourcing fraud, and the safety risks posed by this substandard engine installation. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The RED light is lit on the dashboard for the airbag. Unable to use steering wheel electronic features which helps with and was designed for hands free controls. I am unable to cycle through the electronic features or engage the cruise control due to the steering wheel electronics are in-op. Please help and get a recall started. This is not on the consumer.

[XXX] [XXX] [XXX]; [XXX] [XXX] [XXX] Date: XXX To: National Highway Traffic Safety Administration Office of Defects Investigation (ODI) Subject: Formal Safety Defect Complaint – 2017 Hyundai Sonata Theta II Engine Failure, Excessive Oil Consumption, Intake/Engine Component Failure and Safety Hazard Dear Sir or Madam: I am submitting this formal complaint and request for immediate investigation into the dangerous and ongoing mechanical failures involving my 2017 Hyundai Sonata equipped with the Theta II engine. I believe this vehicle contains a serious manufacturing and/or engineering defect that presents a substantial safety hazard to consumers. My vehicle has experienced a pattern of progressive mechanical failure beginning with abnormal and excessive oil consumption, which appears to be directly associated with malfunctioning engine airflow and intake-related components. Specifically, the lower engine airflow system and intake functionality appear defective, placing excessive strain on the intake manifold system and contributing to cascading engine failures. As a result of these failures, the vehicle has experienced: Severe and excessive oil burning/consumption Intake manifold malfunction and abnormal operating stress Suspected overheating and/or premature head gasket failure Ignition coil failure and electrical shorting/misfires Progressive engine deterioration rendering the vehicle unsafe and unreliable Increased risk of sudden engine shutdown, stalling, fire hazard, or catastrophic engine failure while operating The vehicle has become increasingly unreliable and inoperable due to these conditions. These failures raise significant concerns regarding public safety, especially given the known history of complaints and recalls associated with Hyundai Theta II engine defects. I am deeply concerned that this vehicle may reflect a broader pattern of defective manufacturing, insufficient quality control. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Supplemental Information to Existing NHTSA Complaint involving a 2017 Hyundai Sonata Plug-in Hybrid (VIN: [XXX] ) While traveling at approximately 70 MPH on a heavily traveled highway, the vehicle suddenly and completely lost propulsion without warning. The vehicle rapidly decelerated in traffic, creating a significant safety hazard for my family and surrounding motorists and requiring emergency maneuvering to reach the shoulder. The vehicle was towed to an authorized Hyundai dealership, where diagnostic testing identified multiple high-voltage battery system fault codes: • P0B68 • P0B6D • P0B72 The dealership diagnosed a high-voltage battery system failure requiring battery replacement. The vehicle is currently non-drivable. During my research, I found multiple owner reports involving Hyundai Sonata Hybrid and Plug-in Hybrid vehicles experiencing loss of power, hybrid system failures, limp mode conditions, and propulsion-related incidents. I also learned that Hyundai previously issued Recall 18V166000 involving 2016–2018 Sonata Plug-in Hybrid vehicles due to battery management system and voltage protection device concerns that could result in loss of power while driving. Dealer says does appply for my car. Although my vehicle’s fault codes may differ from those addressed in the recall, both involve battery-related failures capable of affecting propulsion and creating a highway safety risk. My concern extends beyond my individual vehicle. A high-voltage battery or battery management system failure that can cause a complete loss of propulsion at highway speed without warning presents a potentially serious safety risk. I respectfully request that NHTSA evaluate whether similar incidents involving Hyundai Sonata Hybrid and Plug-in Hybrid vehicles indicate a broader safety concern warranting further review. I can provide dealership diagnostic reports, repair estimates, towing records, photos, and videos upon request. Thank you for your consideration, [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

I am writing to report a serious, premature failure of a primary emissions and safety-related component (the catalytic converter) that has occurred as a direct consequence of a known, unaddressed manufacturing defect in Hyundai's Theta II engine. My vehicle has a documented history of excessive engine oil consumption. This inherent manufacturing flaw causes the engine to burn motor oil at an extreme rate, forcing unburned oil directly into the exhaust system. Over time, this oil has fouled and destroyed the catalytic converter substrate, triggering trouble code P0420 and causing a complete component failure. A dealership inspection at Heritage Hyundai Towson (RO #XXX) confirmed "excessive wear" and failure of the catalytic converter. Because the catalytic converter is failing prematurely due to a liquid defect (excessive oil burning) rather than standard wear and tear, it poses an environmental hazard, compromises vehicle emissions control, and can lead to sudden engine stalling or reduced power while driving, presenting an active safety risk. Hyundai Motor America (Case #XXX) has formally denied assistance to rectify this consequential damage, despite full awareness of the underlying engine defect. I request that NHTSA investigate how Hyundai’s ongoing oil consumption manufacturing issues are causing cascading safety and emissions component failures in these vehicles. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The rod bearings failed in the engine. The vehicle is currently at the dealership and is available for inspection. Rod bearing failure can cause complete engine seizure while driving, creating a serious risk of losing vehicle control at any speed. This is a known issue with Hyundai's Theta II engine. Yes. The dealership performed a diagnostic on April 27, 2025 and confirmed rod bearing failure. Yes. The dealership inspected the vehicle and Hyundai corporate opened a warranty case and arranged the repair appointment, initially confirming coverage before later denying the claim without providing documentation. The dealership has also repeatedly failed to provide documentation supporting the denial of my warranty claim despite my requests beginning April 29, 2025. I have also been unable to get callbacks from the dealership after being promised updates on May 1st, May 7th, and after requesting a manager on May 18th. As of May 27, 2025 I have still not received any documentation or a callback. The check engine light came on prior to the failure. I proactively checked and changed the oil, added Lucas oil treatment, replaced the spark plugs, and replaced the battery attempting to diagnose and resolve the issue before bringing it to the dealership. No oil pressure warning light ever appeared. The check engine light persisted despite these efforts which is what led me to bring the vehicle in.

I have a Hyundai Sonata 2017 one year after I bought the car I started having acceleration problems. I have had the throttle changed and the valve gasket cover repaired. On April 15, 2026 the check engine light came on. On April 29th I got theta 2 emissions update installed at Hyundai Auburn, Al. I took it too auto zone the same day the code P1326 was showing up and P0014. On May 5th my car entered limp mode for excessive oil leakage, I got an oil change April 6, 2026. My car has never done that until the update was installed. I get my oil changed every 6 months and also have sent them records. They denied my claim due to lack of maintenance.

Engine failed while driving, Took it to dealership and the engine is seized. We were declined by Hyundai an engine replacement even though the Theta 2 engines have a lifetime replacement warranty because these engines are known to fail. They constantly deny due to 'severe owner neglect' because people do their own oil changes.

The vehicle experienced repeated engine-related failures associated with the P1326 error code, which indicates a potential engine defect. The issue first occurred around February 2023 at approximately 51,500 miles, when a warning light appeared. The problem has recurred multiple times despite inspections and service attempts. In January 2024, a dealership performed a software update related to the P1326 code. Shortly after this update, the engine began consuming excessive oil (approximately 2 liters per 1,000 miles). The condition worsened over time, and the vehicle failed an oil consumption test conducted by a dealership. The issue was confirmed by an authorized dealership, which ultimately diagnosed the engine as failed and requiring replacement in May 2026 at approximately 99,000 miles. The problem has been reproducible, with the P1326 warning code appearing multiple times over the life of the vehicle. This condition creates a significant safety risk because the engine may lose power, misfire, or stall unexpectedly while driving, increasing the risk of a crash, especially at highway speeds or in traffic. The vehicle has already experienced engine misfire and severe performance issues. Warning indicators included the P1326 error code and check engine light, which first appeared in 2023 and recurred multiple times thereafter. The engine oil consumption issue developed after the 2024 service and continued to worsen. The failed engine is currently available for inspection upon request.

On 12/20/25, the car - a Sonata plug-in hybrid - failed to start. When I pushed the "start" button, the dashboard display lit up w many clearly irrelevant error messages. Each time I pressed start, somewhat fewer error messages blasted toward me, and finally, no response at all. On 12/21/2026, the tow driver said it was the 12-volt battery. He gave us a jump start and we drove a few blocks. However, it failed at the turn lane while waiting for the light to turn. We turned it back on, bought a new battery, had it installed. On 12/29/25, my husband was driving. He turned into the intersection with a traffic light. As he was making the turn, the car simply quit. No warning. The car was dead, and blocking traffic! He pressed the start button to turn off the car, then again to turn it on. He was able to complete the turn and parked on the side of the road. By this time it had a "check engine" light on. He then drove slowly the few blocks back to our house. On 12/30/2025, the car was towed to a local mechanic. He said it threw the code PODE7, "almost certainly for a failed High Voltage battery." It was still under warranty, and we had the car towed to the dealership. After keeping it for 2 or 3 weeks, they confirmed the code and that the control panel needed to be replaced. We finally picked up the car (w new control panel) on 2/20/2026. In the meanwhile, we looked up Hyundai control panel repairs on a reddit forum. We found lots of chatter about it. Turns out it's a recognized problem in Sonata and Ioniq EV and PHEV's! Clearly, a car failing in the middle of an intersection, highway, etc is a safety problem and needs to have repair/replacements made BEFORE THEY HAPPEN!

Engine experienced severe metallic knocking and loss of power. A certified Hyundai technician confirmed a FAILED Bearing Clearance Test (RO #354331). Hyundai Motor America is refusing to honor the Engine II Class Action Settlement warranty, citing internal code A99 because the vehicle was purchased at an auction, even though the title is CLEAN. This pose a safety risk of engine seizure and potential fire.

Consistent burning of oil

The failed component is the engine assembly in my 2017 Hyundai Sonata SE with the 2.4L Theta II GDI engine. The failure involves excessive oil consumption and internal engine failure, specifically suspected piston ring deterioration allowing oil to pass into the combustion chambers. The vehicle is available for inspection upon request. Safety was put at risk because the engine was losing oil rapidly. If the oil level drops too low, the engine can seize, stall, or lose power while driving. Sudden engine failure at road or highway speeds could increase the risk of a crash. The issue required constant oil monitoring and made the vehicle unsafe to rely on. The problem was confirmed by both an independent repair shop and a Hyundai dealership. At about 99,813 miles, an independent shop diagnosed oil burning from the tailpipe. I then paid for major repairs, including cylinder head and valve work, but the oil consumption continued. A later independent inspection found internal oil consumption consistent with failed piston rings and oil bypassing into the combustion chambers. The Hyundai dealership performed Hyundai’s oil consumption testing process, including combustion chamber cleaning and rechecking oil level. The vehicle failed and engine replacement was approved. The dealer quoted $11,400-$12,000 for replacement. The vehicle has been inspected by an independent repair facility, a Hyundai dealership, and reviewed by Hyundai Motor America Customer Care under case number 42489659. Hyundai denied assistance, stating the vehicle is outside warranty due to time and mileage. Symptoms first appeared around 99,813 miles and included excessive oil consumption, burning oil from the tailpipe, reduced power/dragging, abnormal rattle/noise during low-speed acceleration, and poor fuel economy. After repairs, the oil level still dropped below minimum quickly. I am filing this complaint because this condition may cause sudden engine damage, stalling, or loss of power while driving.

I am reporting a serious safety issue involving a 2017 Hyundai Sonata Plug-in Hybrid (VIN: [XXX] ), originally purchased in California. While driving at approximately 70 mph on a highway, the vehicle suddenly lost all propulsion without warning and rapidly decelerated. This created a dangerous situation with surrounding traffic and put me and my family at risk. I had to quickly maneuver to the shoulder to avoid a potential collision. The vehicle was towed to an authorized Hyundai dealership in Utah, where it was diagnosed with a failure of the high-voltage battery system. I was informed that the battery requires replacement. This type of sudden loss of propulsion at highway speed is extremely hazardous and could result in a crash, injury, or fatality. There were no prior warnings indicating an imminent failure of this severity. Given the safety risk associated with unexpected loss of propulsion, I am concerned this may represent a broader issue affecting similar vehicles. The vehicle is equipped with an interior camera, and video of the incident can be provided if needed. I respectfully request that this issue be investigated as a potential safety defect. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

See attached document for complaint.

Burns through oil Oil will be black and barely any on the dip stick Cannot make it to recommended oil change miles or date Goes into limp mode

I am submitting a vehicle safety complaint regarding a recurring HEV warning system indicator affecting my 2017 Hyundai Sonata Hybrid that was not properly diagnosed despite multiple service visits to Nalley Hyundai beginning around July or August 2022. During several service visits while the vehicle remained covered under an extended warranty, I reported the HEV warning indicator to the dealership. Each time the vehicle was returned to me, the warning light was no longer illuminated, giving the appearance that the issue had been resolved. I was not billed for these visits. However, I was informed that the dealership could not determine the cause of the warning indicator, and no permanent repair solution was completed. Because this issue involves the hybrid electric system, I am concerned this may represent a safety-related condition affecting vehicle reliability and drivability. The warning indicator has continued intermittently and has now progressed to the point that my vehicle is no longer dependable transportation. I respectfully request that this complaint be reviewed as a potential hybrid system warning indicator concern affecting the 2017 Hyundai Sonata Hybrid.

The contact owns a 2017 Hyundai Sonata. The contact stated that the front driver’s side seat belt failed to lock securely. The contact stated that the seat belt loosened unexpectedly and failed to properly protect the driver while operating the vehicle. The dealer was notified of the failure. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was 102,000.

Care recently became inoperable. The engine was knocking, then stalling and then inoperable. Checked Hyundai website to find Engine Recall describing exactly what my Hyundai was/is experiencing. I brought vehicle to Clay Cooley dealership (39444 Lyndon B Johnson Fwy, 75232) and explained that I see the recall on the Hyundai website describing what my vehicle is experiencing. After their service mechanics review, the Service Department Representative falsely accusing me of the engine failure, stating that I "must not have changed my oil regularly". According to the service department, my 2017 Hyundai Sonata (132,000 miles) is not covered in the engine recall, and I must pay $4,926.53 for the repair. cc: FTC - ReportFraud.ftc.gov Texas Attorney General - Consumer-Protection/file-consumer-complaint

To the National Highway Traffic Safety Administration, I am filing this formal safety complaint regarding a dangerous engine failure incident involving my 2017 Hyundai Sonata Plug-in Hybrid. Description of Incident: While traveling on CA-85 near Mountain View, California, at approximately 65 miles per hour, the engine suddenly and without warning lost all power. The vehicle began to slow down involuntarily in active highway traffic, creating an immediate and serious risk of rear-end collision. The driver had no ability to maintain safe highway speed or accelerate out of danger. The vehicle had to be towed from the scene to the dealership. There was no warning light or prior indication that engine failure was imminent. The failure was sudden, complete, and occurred at highway speed in heavy traffic conditions. Safety Risk to the Public: This incident represents a significant and ongoing public safety hazard. A sudden, unpredictable loss of engine power at highway speed — with no prior warning — places the driver, passengers, and surrounding vehicles at serious risk of collision. This is not an isolated mechanical inconvenience; it is a life-threatening failure mode. Known and Documented Defects: The 2017 Hyundai Sonata Plug-in Hybrid has been the subject of multiple recalls and class action litigation related to engine defects. My incident is consistent with the known failure patterns documented in those proceedings. Despite this history, Hyundai Motor America has denied my warranty claim, citing missed services — a characterization I dispute, as the vehicle was serviced exclusively at an authorized Hyundai dealership whenever the onboard system indicated service was due, and no technician ever identified or disclosed any engine damage during those visits. Request to NHTSA: I respectfully request that NHTSA: 1. Open or expand an investigation into engine failure incidents in the 2018 Hyundai Sonata Plug-in Hybrid 2. Investigate whether a recall is warranted

The contact owns a 2017 Hyundai Sonata. The contact stated that while his wife was driving at an undisclosed speed, the vehicle experienced engine failure. The vehicle made a knocking sound prior to the failure. No warning lights were illuminated. The vehicle was towed to the residence and eventually towed to the dealer, but was not diagnosed or repaired. The dealer acknowledged the engine failure and that the failure was a common failure. The dealer declined the repair due to a lack of service records. The contact was offered a combustion cleaning; however, the vehicle was disabled. The manufacturer was notified of the failure. The approximate failure mileage was 95,000.

The contact owns a 2017 Hyundai Sonata. The contact stated that the vehicle had experienced excessive oil consumption, caused by engine rod bearing failure. The engine rod bearing failure caused excessive oil consumption and premature spark plug fouling, requiring the frequent replacement of the spark plugs. The dealer was notified of the failure. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was approximately 132,000.

Sun roof flew off while driving, the metal framing was twisted and dent. Sun Roof was closed at the time. Pictures were sent to insurance company but no one has looked at it yet. No warning. Sun roof was working properly.

I have a 2017 hyundai sonata sport,it started using a lot of oil,one day I was driving and it just lost speed and the car just started jerking. I checked the spark plugs and oil had gotten on them. I changed the spark plugs,drove it for about 2 weeks and it did it again. I was constantly having to put oil it and changing the spark plugs every 2 weeks. The check engine light would come on every time this happened. I took it to a hyundai dealership they first wanted to do a oil test which they realized would not work because it was using to much oil ,second they wanted to do some other test that would cost almost $300 dollars which would still not determine if I would be eligible for the recall. Can i get some help please,please

Here is your updated review with that included: ⸻ I am very disappointed with Hyundai Motor America and the service I received at Hyundai of Renton. I own a 2017 Hyundai Sonata and received a letter about a required software update and ignition cylinder protector due to known theft issues. I went to the Renton dealer for the recall service. They performed the software update and were supposed to install the ignition cylinder protector. Unfortunately, my car was later stolen because of this exact issue. The ignition was damaged during the theft, and I had to replace it myself just so I could drive the car. When I returned to the dealer, they refused to install the ignition cylinder protector, saying the ignition was broken. It was broken because of the theft — which happened due to Hyundai’s known defect. After the recall software update, my key fob also stopped working properly. I went back to the dealership, and they refused to fix or properly reprogram my key fob. On top of that, the service manager, John, was very rude and unprofessional. This has been the worst experience I’ve had with a vehicle and a dealership. Because of this situation. Very disappointed.

While driving around 45 mph, the steering wheel locked up and car came to a hard stop. Luckily cars swerved to avoid me. This was the second time it happened. The first time I was in a parking garage and the steering wheel locked up. After restarting the vehicle, the steering wheel worked again. The dash showed no fault codes or engine light. I found out there is a service bulletin and took it in to the dealer. Once there, the confirmed it was the power steering and is covered by the service bulletin and extended warranty. However, because the bulletin requires the dealer to clear code to try and reproduce it, I have to pick up vehicle because they could not reproduce the fault code. So now I have to drive the vehicle knowing their is a service bulletin for the problem and have it happen again before it is fixed. There is an extremely high likelihood of injury considering you lose all power at wheel and car continues to move.

My 2017 Hyundai Sonata Hybrid has a permanent and recurring DTC P1326 (Knock signal range/performance) from the Knock Sensor Detection System (KSDS), indicating potential connecting rod bearing wear in the Nu 2.0L engine. The vehicle enters limp mode (reduced power, limited acceleration/speed) on the highway under load, with hard engine vibration, tinkling/knocking noise from under hood, and significantly reduced MPG. These symptoms create a serious safety risk: sudden loss of power at highway speeds (e.g., 50+ mph) makes it difficult to maintain speed, merge, or avoid hazards, increasing crash risk or stranding in traffic. In rare cases, bearing wear can lead to engine seizure or failure. The problem first appeared summer 2024 at approximately 115,000 miles. The Check Engine Light illuminates (cristmass tree), and limp mode triggers during highway driving. I have an OBD scan showing confirmed, pending, and permanent P1326, plus related hybrid communication codes (U0293, U1004) likely secondary to the protection mode. The vehicle has been inspected multiple times (four visits) by a Hyundai dealer. Each time they scanned the code, performed basic checks, but stated “engine is working normal, no road vibration, nothing” and did not resolve the issue. The code returns immediately after clearing. I replaced the knock sensor, engine mounts, spark plugs, ignition coils myself—did not fix it. Dealers did not perform the full bearing clearance test or follow TSB 22-01-023H (Service Campaign T6G) procedure as required for this known issue (related to Recall 209 and Campaign 966). The component (engine/connecting rod bearings) is still in the vehicle and available for inspection. No police, insurance, or other parties have inspected it beyond the dealer. This matches a widespread known defect in 2011–2019 Sonata Hybrids (bearing wear triggering P1326/limp mode).

This car is becoming more of a headache than it’s worth. Turned the car on, My car started shaking and my check engine light came on. then I got this message “A possible condition with your engine control system has been detected on a 2017 Hyundai Sonata”

Car just sputtered and then the engine stopped working in cyclinder 2

My car stayed with up to date oil changes and everything. One day I noticed it was leaking oil and had to stay on top of adding oil. When took to a mechanic they said my motor was blown and needed a new one. I took very good care of this car and it’s crazy that I need a new motor after babying the car.

Was just driving and lost steering, basically very hard to turn the wheel. Traction control light and a red steering wheel light came on.

My 2017 Hyundai Sonata is exhibiting a severe metallic knocking noise and metal debris in the engine oil—primary indicators of the Theta II engine defect (NHTSA Campaign 17V578). These symptoms indicate imminent engine failure, posing a significant stall and crash risk. On or around 8/20/25, I took the vehicle to Earnhardt Hyundai-San Tan. I informed the technician of the oil burning and metal shavings. They refused to perform the recall repair and charged a $200 diagnostic fee for an inspection related to a federally mandated safety recall. Under federal law (49 U.S.C. Chapter 301), recall remedies must be provided at no cost to the owner. Furthermore, components were not reassembled correctly during the inspection. The vehicle is now leaking oil onto my driveway and has been rendered inoperable. It has not been driven since I picked it up on August 25, 2025. I am requesting that Hyundai be compelled to perform the recall remedy and reimburse the unauthorized diagnostic fee.

Please see the attached paperwork and I have more if needed. I am not receiving any help from the local Hyundai dealership in which I purchased the car, and I have reached out to the main Headquarter. This is the 2nd Hyundai I purchased, and I was not made aware of the oil consumption issue.

My vehicle has a documented excessive oil‑consumption defect. After a 1,000‑mile oil‑consumption test performed by a Hyundai dealership, the engine was found to have consumed 2.8 quarts of oil, which is far above normal and poses a safety risk. The dealer referenced TSB 23‑EM‑008H and recommended a chamber cleaning but could not guarantee it would resolve the issue. Hyundai Motor America declined to cover the repair and refused to escalate my case. This level of oil consumption is consistent with known Theta II engine defects that have led to engine seizure, stalling, and fire in other vehicles. I am reporting this as a safety concern due to the risk of sudden engine failure while driving.

While driving car stuttered check engine light and check hybrid system flashed. Check engine lights stayed on until getting home. Next day. I scanned and code p0b68 was set.

While driving at a high rate of speed propulsion to the vehicle suddenly and without warning ceased, the electric and internal combustion engine were non-responsive (ICE stopped; hybrid motor didn't provide propulsion), the warning light said "Check Hybrid System. Turn off engine" I was put at risk because I was traveling at highway speed and was given no warning before the vehicle shut down. This has occurred nine times, I've reported all to Hyundai, they have had the car in the shop three times, the issue is not fixed. No, despite ODB2 error codes, the car has not shut down while a dealership is driving it. Yes, the vehicle has been inspected multiple times by Hyundai. Yes, always "Check Hybrid System. Turn off engine", in almost all cases the check engine light comes on after that, and in some cases additional lights such as "auto hold". This first occurred in Dec 2023, I was told the car was fixed (it wasn't) and happened again in October 2024. I haven't been able to drive my car since then.

While driving the 2017 Hyundai Sonata Plug-In Hybrid, the car will begin to stall, a rapid number of audible beeps will start, the "Check Hybrid System" notification will pop up on the dashboard, and the "Check Engine Light" appears.. The car therefore cannot be driven anymore, and I am forced to pull over to the side. In order to fix the issue temporarily, I need to turn the car off and turn it back on again. Once this is completed, both the "Check Hybrid System" and the "Check Engine Light" disappears and the car can be driven again. An OBD Scanner is unable to find exactly what is going on as the "Check Hybrid System" and the "Check Engine Light" no longer appear. This has happened 4 times now within the span of 3 months. The people at risk are me (the driver), my passengers, and potentially everyone else on the road in my nearby vicinity as the problem occurs. This problem has been confirmed by the dealer in their Hybrid vehicles. This vehicle has not been inspected yet but that is an ongoing process.

I was driving the vehicle with 2 other occupants onboard on [XXX] towards US-101. The EPS warning light already came on after entering [XXX] from [XXX], but initially, I didn't think it was much of an issue. As I merged to the right lane in preparation of entering the highway, the steering began to feel very stiff, so I immediately made a right turn into a local street when there was a little bit of steering left. As soon as I pulled over, the steering locked up completely, and both the EPS warning light and the dash display's lane-departure system warning were activated. Luckily no other vehicle or humans were endangered at the time. I put the car into park and powered it off. When I powered it back on again several minutes later, the issue resolved itself and I was able to continue driving with normal steering, and steering remained normal after several power on/off cycles which included both local and highway driving. Come to think of it, ~3 months before this incident happened, I already noticed occasional stuttering of the steering wheel and humming of the EPS assembly when the car is stationary or at low speed. I took the car to a third-party repair shop on the next day since the Hyundai dealership appointment is a week away at the earliest. They ran diagnosis before telling me that the steering sensor in the EPS motor assembly failed, and this happened very frequently for 2017 Sonata Plug-in hybrids. This happens so often, apparently, that Hyundai issued service bulletin [XXX], but this very much looks like a recall to me, as when the system fails, steering is lost completely, and could cause great harm to myself as well as the occupants onboard, not to mention other vehicles around me. I was lucky that it happened before I entered the highway and also had a place to pull over. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Vehicle lost power in freeway. Complete power failure. Early crashed into. Vehicle coasted to off ramp and towed away.

About 3 weeks ago I had just left my house, battery fully charged and gas tank full. I was coming down a hill to a stop sign and started braking. Suddenly the car seemed to lose power and essentially stopped moving. There was an error on the dash saying "hybrid system failure". There was barely able enough power to slowly pull the car over to the side of the road. I turned off the car and checked the battery in the trunk - I didn't see any obvious concerns. My husband got there 10 minutes later and we tried turning the car on again. It came on fine but there was an engine warning light. We were able to drive it without difficulty back to my house. I was unable to get a timely appointment at my local Hyundai dealer, so a couple days later My husband drove it to a local garage to see if they could figure out what the problem was. When he turned the car on again the engine light was no longer on. However, at the garage they were able to pull up a history of the car alerts and it confirmed that it said hybrid system failure. I have done some research online and it sounds like there was a recall on Hyundai sonatas hybrids for 2017 but I did not see a recall for the plug-in version of the hybrid. I searched online, however, and there were many other owners of Hyundai sonata plug-in hybrids that reported the same incident. I am hoping that a recall gets is issued for the plug-in hybrid as well so that more owners don't have the same problem. If I had been driving on the highway at 65 mph in a middle lane and my engine suddenly lost power it could have been fatal. Oh - one other recent problem I had that I'm not sure is related is that my car recently started losing electric miles very quickly. From the time it was purchased until a few months ago, it was losing plug-in miles at about 1 mi per year (i.e. each year a fully charged battery gave me 1 mile less). Then about 6 months ago it started losing electric miles very quickly - about 1/mo. Dealer said it was normal aging.

Occurrence: This has been a recurring issue for over a year (over a year, might be closer to two years now) for our PHEV Sonata. It has happened approximately 10 times. Problem: Total engine shutdown when driving the car. "Shut down engine" type error message pops up and cannot accelerate. Steering still works, but it can be hard to pull over due to lack of engine power. The car can be restarted after shutting down, but must first come to a complete stop and into Park. Safety Issue: The car stops working. Obviously, this would be quite dangerous on a busy road, a highway, or if you were taking a left turn, etc. Confirmation: The dealer indicates that the hybrid battery is a problem and should be replaced. However, due to supply chain issues, we have been waiting for over a year for the replacement. **** Reproduction Steps: **** We have found that it is most likely to happen with a fully charged battery and a sudden braking action. I suspect the issue happens when trying to charge the battery but due to its condition, it shuts down instead. It tends to happen: 1) Full Charge: Battery is fully charged overnight or "topped up" to full charge 2) Sudden Braking: Having to brake hard, such as being cut off. We have found that adjusting charging and driving habits has reduced but not eliminated the issue. Suggestion: I would suspect that having some electrical component to prevent a sudden overcharge might eliminate this problem (shunting excess current or turning off regenerative braking for sudden stops). Warning Messages: A warning message is seen, but it happens at the same time the engine is shut down and disappears before you could take a picture of it (as you are busy trying to do an emergency pull over).

My 2017 Hyundai hybrid PHEV vehicle stuttered and failed to accelerate when the gas pedal was depressed and a warning light indicated a problem which was confirmed as a failed battery in January 2023. I was advised by the Hyundai Sonata service center 13 weeks ago that the vehicle was unsafe to drive due to a defective battery. They have not been able to replace the battery or provide an estimate of when the replacement battery will be delivered. The battery has a lifetime warranty but the Hyundai company and dealership is not providing a loaner vehicle or reimbursing me for rental vehicle while the unsafe vehicle sits in the service center for more than 3 months. Please help.

Problem began Dec. 2021. Has occurred on 16 occasions since then. Warning light "Check Hybrid System; Turn off Engine" comes on while driving. The car then shuts off the engine and there is a 100% loss of motive power. Sometimes is associated with very rough braking with the car "knocking'." On 3 occasions there has been partial/near complete loss of braking power. All incidents have occurred while under power, so far all while under 45 mph. No accidents yet. Two near collisions from the rear. Hyundai was notified of the problem Dec. 2021/Jan. 2022. After a month of testing they stated the car needed a new plug-in hybrid battery. One was not available and due to "supply chain issues" is still not available 15 months later. Dealership provided a loaner vehicle Jan to Sept. 2022. They requested their car back and Hyundai initially agreed to cover the cost of a rental car. I rented a car for 6 weeks in Sept.-Oct. 2022 at which point a new case manager informed me that Hyundai would not pay for a rental vehicle any longer (note: they did reimburse me the cost of those 6 weeks rental). Hyundai is well aware of the safety issues involved in driving this vehicle. However, they have chosen to ignore them. Their attorney, in a letter to the Ohio Attorney General's Office, blamed the lack of a plug in hybrid battery on supply chain issues (letter was Nov. 2022, at which time the battery was supposed to be available March 2023) and only stated that my vehicle was "drivable." Another warning message "High System Temperature; Switching to Hybrid Mode" has been occurring for a couple of years periodically. Since October 2022, the malfunction indicator lamp is always on and 99% of the time the "Check Hybrid System!" warning light also comes on after about a minute after starting the vehicle. On 3 other occasions the vehicle has entered into "limp home mode" instead of complete shutdown.

The vehicle has stalled in traffic numerous times since I bought it in 2016 creating a traffic safety issue. Without warning the lights on the dash will flash and the car dies. I have worried each time that traffic behind me would collide with my car. #1 1 1/2 years into ownership this occurred. They replaced part of the EV charging system that was overheating on the cars. (RECALL) # 2 1 /2 years into ownership the air-conditioner failed and the car stalled in traffic due the air-conditioner failing. (REPLACED UNDER EXTENDED WARRANTY) # 3 Last year I complained that a Hybrid Overheat Message would come on switching to EV mode and the transmission felt like it was slipping occasionally, and the battery only held 20 miles of charge, rated for 27. They refused to change the battery system under the lifetime warranty. #4 Last summer car stopped charging (REPLACED INVERETER UNDER EXTENDED WARRANTY) This month car stalled on the roadway, lights flashed on dashboard. Could have been rear-ended, Had to coast to a stop and restart the car. Took to dealer the said the replaced an EV computer for 5K (REPLACED COMPUTER UNDER EXTENDED WARRANTY) 3 days later same issue, stalled on busy street without warning. Took to dealer and the replaced the cars main battery, charging me $450.00 3 Days later it stalled again without warning in traffic, It's not back in the shop. THIS VEHICLE HAS MAJOR SAFETY PROBLEM. IT'S EXTREMELY DANGEROUS TO HAVE A CAR STALL IN TRAFFIC WITHOUT ANY PRE-WARNING. THE DESIGN IS DEFECTIVE. THE CARS NEED TO BE RECALLED AND BOUGHT BACK AT FULL PRICE BY THE HYUNDAI.

The engine started knocking on the freeway and all the lights in the car went off. The engine failed and I barely made it off the freeway. I was almost hit by two cars trying to get to a safe place. The engine has the same issue as the other morsels that have recalled the engine for the same rod failure issue but Hyundai has not extended the recall to the plug in hybrid. This model also bends to be recalled because it is a danger to all owners and other drivers. Hyundai declined to repair the defective engine.

On cold mornings, during the first start of the day, and while going downhill, the internal combustion engine comes on while running on electrical power from the battery. This is understandably to heat up the engine to ideal temperatures. But within a minute, the car gives a hybrid battery error, fully loses power requiring to be stopped immediately. This is obviously dangerous anywhere but particularly downhill. The car requires to be restarted after pulling over 1-3 times until the engine / battery reach ideal temperatures. Then the car runs as expected. The dealership has been unable to diagnose the issue and chalked it up to an unrelated recall - which has been fixed, but the issue still occurs risking the safety of the people inside the car and around.

While driving on surface streets (10-15 MPH) about 5 minutes out from our house, the accelerator stopped working properly and a warning popped up along the lines of "Hybrid HEV warning: Please shut off engine and restart." Since there were no other cars behind us, we were able to thankfully pull over without too much trouble. However, if we had been on a highway this would have been incredibly dangerous, as we would have lost speed quickly and had no safe way to pull over. There were no warnings prior to this happening on that day. The car just sudden stopped working and then lights popped on. Using an OBD reader, the issue code was P0DE7: Hybrid/EV Battery - Cell Voltage High. We are going to the dealer at the earliest appointment to have it looked at, and the car is clearly not safe for anything but surface roads with easy pull-offs. Related Items: A week or so ago, we had an incident where the car was a bit sluggish to accelerate after a right hand turn (e.g., needed to take foot off the gas, then put it back on after a moment to accelerate). However, no check engine light came on and the car ran fine after. A second potential related item was that the expected mileage on battery-only had reduced from about 27 to 23 miles on a full charge. This occurred within the last two months before this issue.

The contact owns a 2017 HYUNDAI Sonata Plug-In Hybrid. The contact stated while driving approximately 35 MPH, the vehicle started making a loud knocking sound. The contact pulled over and noticed an excessive amount of oil underneath the front of the vehicle. The contact took the vehicle to a certified mechanic who diagnosed that there was a hole in the engine block. The mechanic showed the contact a piece of metal that had fractured from the engine. The contact stated that three days later while driving approximately 25 MPH, the vehicle stalled. The vehicle was towed to the dealer who confirmed that the vehicle was not included in NHTSA Campaign Number: 21V727000 (Engine). The vehicle had not been repaired. The manufacturer was made aware of the failure. The approximate failure mileage was 76,000.

On August 31st 2021, While driving my 2017 Hyundai Sonata PHEV on interstate 95 the check engine and hybrid system warning lights came on and the car simultaneously lost power for 3-4 seconds, which caused a decrease in speed from 65 to approximately 50 mph. There was a tractor trailer behind me but thankfully it braked to avoid striking my car. The car regained partial power and I was able to drive it home. I took the car to the dealership to have it repaired. The dealer diagnosed a faulty battery management system, and replaced this component after 17 days. On September 25, while driving on a street the car once again lost power for 3-4 seconds, with the check engine and hybrid system lights simultaneously illuminated. There was a recall on my vehicle several years ago to prevent this dangerous problem. I had the car repaired at that time but clearly the problem was not fixed as my car has subsequently lost power on two separate occasions, in a manner that could have easily caused a crash.

The trunk will not open by any means, at times it can be opened, but the emergency release does not work. If anyone gets in, they cannot get out, especially with the Hybrids which do not have fold down back seats. Federal mandate states the trunk must have an operational emergency release, but with the trunk latch issue, the emergency release does NOT work.

THE TRUNK LATCH NOT LOCKING. OPENED TRUNK IN DRIVEWAY, TRIED TO CLOSE TRUNK AND IT WOULDN'T LOCK/CLOSE.

TL* THE CONTACT OWNS A 2017 HYUNDAI SONATA PLUGIN HYBRID. THE CONTACT STATED WHILE DRIVING 50 MPH, SHE HEARD AN ABNORMAL SOUND. THE CONTACT STATED THAT THERE WAS NO WARNING LIGHT ILLUMINATED. THE CONTACT DROVE TO HER RESIDENCE. THE CONTACT STATED SHE HAD THE VEHICLE TOWED TO HARRISONBURG FORD, INC. (3155 S MAIN ST, HARRISONBURG, VA 22801; (540) 434-0700), WHERE IT WAS DIAGNOSED WITH NEEDING THE ENGINE TO BE REPLACED. THE VEHICLE WAS REPAIRED. THE MANUFACTURER HAD NOT BEEN INFORMED OF FAILURE. THE FAILURE MILEAGE WAS APPROXIMATELY 75,000.*DT

I WAS DRIVING MY HYUNDAI 2017 SONATA PLUGIN HYBRID ON THE HIGH WAY IN HEV MODE AND SUDDENLY I FELT SEVERE VIBRATION IN MY CAR. THEN I CHANGED MY ENGINE TO EV MODE AND IT WAS FINE. ENGINE LIGHT CAME ON. EVERY TIME THE GAS ENGINE CAME ON THE CAR STARTED VIBRATING AND NON RESPONSIVE TO GAS. I DROVE ABOUT 10 MORE KM TOWARDS HOME ON ELECTRIC ONLY ENGINE AND THEN GOT IT TOWED TO THE DEALERSHIP. IT FELT LIKE ENGINE LOST ITS POWER. I RECENTLY CHANGED THE VOLTAGE PROTECTION DEVICE ON THE CAR AS A RECALL. ALL SERVICES WERE DONE ON TIME AND CAR HAD ONLY 33000 KM.

THE SHARK FIN ANTENNA COVER CAME OFF THE VEHICLE. WHEN I PARKED THE CAR, AFTER DRIVING ON THE HIGHWAY, I NOTICED THAT IT WAS GONE. THIS DEFINITELY CAN POSE A DRIVING HAZARD IF IT COMES OFF THE VEHICLE WHILE DRIVING ON THE HIGHWAY. I NOTICED THAT WHAT WAS LEFT OF THE BASE MOUNTS APPEARED TO BE CRACKED WHICH RESULTED IN THE FIN BREAKING FREE. THIS DEFINITELY APPEARS TO BE A MANUFACTURING DEFECT. IT'S APPROXIMATELY A $500 COST AT THE DEALER TO REPAIR. THIS SHOULDN'T HAPPEN AFTER TWO YEARS OF CAR OWNERSHIP. IT WILL GET VERY COSTLY TO REPLACE THIS AT THE DEALER EVERY TWO YEARS. BASED ON OTHERS' EXPERIENCES, THIS APPEARS TO BE A COMMON OCCURRENCE WITH THIS VEHICLE.

WHILE VEHICLE IS IN MOTION AT VARIOUS SPEEDS WITH CRUISE CONTROL ENGAGED CLIMBING UP ON HILLY OR STEEPER GRADES THE VEHICLE ACCELERATES ON THE DASH AT NEARLY 100 PERCENT POWER ACCORDING TO THE HYBRID TACHOMETER. THIS INCREASE IN POWER SURPASSES WELL OVER THE SET CRUISE SPEED. FROM WHAT I HAVE NOTICED ITS 6-10 MPH CLIMBING PAST MY SET SPEED. THERE IS ALSO A LONG DELAY IN POWER RESTORATION AFTER COASTING DOWN HILLS. I FOUND IT TO BE EXTREMELY DANGEROUS WITH THE VEHICLE AT 100 PERCENT POWER BECAUSE IT COULD CREATE A SITUATION IN WHICH YOU COULD POSSIBLY REAREND ANOTHER DRIVER OR LOSE CONTROL IN NORMAL OR ADVERSE DRIVING CONDITIONS, RESULTING IN INJURY OR LOSS OF LIFE. IN ADDITION THE ISSUE COULD LEAD TO A TRAFFIC INFRACTION. MY STATE HAS A LOT OF SPEED CAMERAS. THIS PROBLEM HAVE RESULTED FROM THE RECENT RECALL WHERE HYUNDAI INSTALLED A NEW BATTERY MANAGEMENT SYSTEM. THE VEHICLE HAS APROXIMENTLY 16400 MILES ON IT.

THIS IS THE PLUGIN HYBRID MODEL. THE LITHIUM ION BATTERY CANNOT BE CHARGED SOMETIMES DUE TO OVERHEATING CONDITION. IF THIS IS NOT FIXED, IT MIGHT CAUSE A FIRE OR EXPLOSION. SOMETIMES, IT WILL NOT LET YOU CHARGE. IT WILL NOT EVEN LET YOU TURN OFF THE CHARGE SCHEDULE TO CHARGE. SOMETIMES, IT STOPS CHARGING DUE TO THERMAL PROBLEM. HYUNDAI IS NOT TAKING RESPONSIBILITY TO FIX THIS. ATTACHED PHOTO DOCUMENTED THAT IT DID NOT ALLOW ME TO SWITCH OFF THE CHARGE SCHEDULER TO START CHARGING. I HOPE HYUNDAI WILL ADDRESS THIS PROBLEM BEFORE THE CAR BURNS UP OR EXPLODES.

2017 HYUNDAI SONATA PLUG IN FEATURE FORWARD COLLISION WARNING ON FRONT STICKER SHOULD HAVE ALSO SAID IT ONLY WORKS ABOVE 25MPH AND IT DOES NOT ACTIVATE WARNING SOON ENOUGH SO I THINK ITS CRASH ZONE AND SHOUDL BE ADJUSTABLE AND TESTABLE IT IS NOT NTSB I HOPE CAN HELP MANUFACTURE A STANDARD TERMINOLOGY WHEN IT COME TO SALES AND RELEASE OF HYUNDAI LIABLE IN CASE FAILURE , YES I KNOW THEY WILL NOT COVER FAILURE UNDER MANY CONDITIONS, BUT THE SYSTEM I BROUGHT TO HYUNDAI 2X ONE IN JULY 2017 AND ONE IN MAR 2018 I WAS TOLD FRONTSIDE COLLISION WORK , THERE ARE NO ADJUSTMET FOR DISTANCE VS SPEED TECH JUST TAKE ME FOR RIDE ALMOST COLLIDE WITH THE CAR BEFORE THE COLLISION WARNING CAME ON IT SHOULD HAVE COME ON WITHIN 1-2 SECOND RULE, AND HYUNDAI HAS CHANGE THE SYSTEM FOR YEAR 2018 ,, I'M WORK WITH HYUNDAI TO GET PROPER LABEL , AND RETURN CAR FOR NTSB THE STICKER SHOULD BE MADE TO STATE TYPE OF SYSTEM AND HYUNDAI SHOULD ASK CONSUMER TO SIGN LIABLE RELAEASE THAT SYSTEM WONT ALWAYS WORK, HYUNDAI IS WORK WITH ME, SO THANKS, BUT NTSB SHOUD TEST FRONTSIDE COLLISION SYSTEMS RATE THEM TECHS SHOULD NOT HAVE TO DRIVE THE CAR INTO A CRASH ZONE TO TEST IT, AND I SHOULD BE TOLD SYSTEM NOT WORK<25MPH EVASIVE SALE BUT HYUNDAI WORK WITH ME FYI EXAMPLE OF GOOD SYSTEM IS MOBILEYE 630 FOR FRONTSIDE

TL* THE CONTACT OWNS A 2017 HYUNDAI SONATA HYBRID. WHILE DRIVING APPROXIMATELY 20 MPH, THE FRONT SIDE COLLISION WARNING SYSTEM FAILED TO FUNCTION. THE VEHICLE WAS TAKEN TO STEVENS CREEK HYUNDAI (4425 STEVENS CREEK BLVD, SANTA CLARA, CA 95051), BUT THE FAILURE WAS UNABLE TO BE DIAGNOSED. THE VEHICLE WAS NOT REPAIRED AND THE FAILURE RECURRED. THE MANUFACTURER WAS NOT CONTACTED. THE APPROXIMATE FAILURE MILEAGE WAS 13,000.

THIS IS MY FIRST TIME BUYING A BRAND NEW CAR IN MY MID 40'S. I PURCHASED THE CAR (PLUG IN HYBRID) WITH ONLY 25 MILES ON MARCH 15, 2018 AND AFTER 7 DAYS AND 353 MILES LATER, UPON DRIVING AND COMING TO A STOP IN THE CITY OF PHILADELPHIA, PA, THE CAR STALLED AND LOST POWER. WARNING MESSAGE "CHECK HYBRID SYSTEM." I HAD TO STEP ON THE GAS PEDAL ALL THE WAY DOWN TO THE FLOOR AND WAITED A SECOND OR TWO IN ORDER FOR IT TO MOVE AT A TURTLE'S PACE. FORTUNATELY, I WAS ABLE TO FIND A SAFE SPOT TO PARK THE CAR. IT WAS TOWED TO A LOCAL HYUNDAI DEALERSHIP NEAR ME AND AS OF YESTERDAY, 3/27, NO DIAGNOSTIC FINDINGS. I HAVE NOTIFIED HYUNDAI MOTOR AMERICA AND THEY HAVE OPENED A CASE#. I HAVE ALSO REACHED OUT TO THE SELLING DEALER TO HELP ME WITH THIS MATTER. THIS IS EXTREMELY UPSETTING AND DISAPPOINTING, ESPECIALLY FOR ME AS NEW CAR BUYER!!!

14 MARCH 2018 10:30 AM, 70 MPH ON US 101 TO SAN FRANCISCO, HEV MODE, RAINY WEATHER, 4 PASSENGERS FOR A BUSINESS MEETING. CAR STEERING SHUDDERED AS IF THE TIRES SLIPPED AND SPUN ON THE WET PAVEMENT. ESC, BRAKE, AND AUTO HOLD LIGHTS TURNED YELLOW. WAS ABLE TO DRIVE THE CAR NORMALLY TO REACH DESTINATION, PARKED, ATTENDED MEETING, AND STARTED DRIVING BACK HOME WITH MY PASSENGERS AT 3PM. ESC, BRAKE, AND AUTO HOLD LIGHTS WERE STILL ON. HEV MODE. 30 MINUTES LATER, I-280 AT 65+ MPH, ENGINE POWER DRASTICALLY REDUCED ABRUPTLY, CAR STARTED TO SLOW DOWN AND BECAME UNRESPONSIVE TO THE GAS. TURNED ON EMERGENCY FLASHERS AND WITH GREAT DIFFICULTY IN THE EVENING RUSH HOUR COMMUTE TRAFFIC, MANAGED TO SHIFT RIGHT THREE LANES AND TAKE THE NEXT EXIT, WENT INTO A PARKING LOT AND STOPPED THE CAR. CONSULTED MANUAL FOR ANY MEANINGFUL ACTIONS. STARTED CAR BACK UP. MIL LIGHT ALSO CAME ON ALONG WITH MESSAGE TO TAKE CAR TO DEALER. RAN VEHICLE DIAGNOSTICS AND GOT 'A POSSIBLE CONDITION WITH THE ECS HAS BEEN DETECTED AND A FULL SYSTEM CHECK IS RECOMMENDED SOON'. STARTED DRIVING CAR AGAIN. SAME LACK OF ENGINE POWER. DROVE THROUGH LOCAL ROADS AND COUNTLESS MANY TRAFFIC LIGHTS AND REACHED HOME AFTER 4 HOURS (NORMAL = 1 1/2 HOURS). AT HOME, PLUGGED CAR IN FOR CHARGING. CHARGING STARTED NORMALLY. AROUND 10PM, WANTED TO TAKE A PICTURE OF ALL THE LIGHTS, SO PULLED CHARGING CABLE OUT AND STARTED CAR. ALL LIGHTS WERE OFF EXCEPT MIL! DECIDED TO TEST DRIVE AND FOUND NO LOSS OF POWER. TOOK IT TO NEARBY FREEWAY, FLOORED GAS PEDAL. CAR RESPONDED WITH FULL POWER! NEXT DAY MORNING, DRIVING CAR TO DEALER, HEV LIGHT AND CONTINUOUS WARNING BEEP CAME ON, JUST A MILE AWAY FROM HOME.

TL* THE CONTACT OWNS A 2017 HYUNDAI SONATA PLUG-IN HYBRID. WHILE DRIVING APPROXIMATELY 20 MPH AND ABOVE, THE CRUISE CONTROL CAUSED THE VEHICLE TO ALMOST CRASH INTO THE PRECEDING VEHICLE. THERE WERE NO WARNING INDICATORS ILLUMINATED. THE DEALER WAS NOT CONTACTED. THE MANUFACTURER WAS NOT MADE AWARE OF THE FAILURE. THE FAILURE WAS NOT DIAGNOSED. THE CONTACT WAS TOO SCARED TO DRIVE THE VEHICLE. THE FAILURE MILEAGE WAS 6.

ON 3/15/2017 AROUND 8AM, I STARTED MY CAR TO LEAVE FOR WORK AND THE CAR SHOWED A WARNING "CHECK HYBRID SYSTEM" AND THE CORRESPONDING WARNING LIGHT CAME ON. THE GASOLINE ENGINE ALSO STARTED RIGHT AWAY AND STAYED ON, EVEN THOUGH THE EV BATTERY WAS FULL. THE ENGINE REMAINED ON THROUGHOUT MY COMMUTE TO WORK AND BACK TO HOME IN THE EVENING. I PLUGGED THE CAR IN MY GARAGE FOR CHARGING OVERNIGHT WITH THE TIMER SET TO START THE CHARGING AT 10PM. AROUND 10:45PM, MY WIFE AND I OPENED THE INTERNAL GARAGE DOOR FROM INSIDE THE HOUSE AND IMMEDIATELY SMELLED EXHAUST FUMES AND HEARD THE ENGINE RUNNING. I OPENED THE GARAGE OVERHEAD DOOR RIGHT AWAY AND UNPLUGGED THE CHARGING CABLE WHICH TURNED THE ENGINE OFF. JUST TO BE SURE, I PLUGGED THE CABLE IN AGAIN AND TURNED OFF THE TIMER TO RESTART THE CHARGING IMMEDIATELY. AS SOON AS THE CHARGING STARTED, THE ENGINE CAME ON AND AFTER A FEW SECONDS STARTED REVVING UP ALSO. I IMMEDIATELY UNPLUGGED THE CHARGING CABLE AND ENGINE STOPPED. I TOOK THE CAR TO THE DEALER TODAY AND AM WAITING TO HEAR BACK FROM THE DEALER. I THINK THIS IS A POTENTIALLY SERIOUS SAFETY ISSUE AND HENCE I AM REPORTING IT.

FIRST EXTENDED DRIVE OF NEW CAR, CHECK ENGINE LIGHT CAME ON. TOOK IT TO DEALER FOR SERVICE, WAS TOLD I HAD "BAD FUEL" THAT THEY TESTED A SAMPLE AND FOUND E85 (ETHANOL) IN IT, WHICH IS NOT COVERED BY HYUNDAI NEW CAR WARRANTY FOR PLUG-IN HYBRID ELECTRIC VEHICLES. I PAID $828 TO HAVE FUEL DRAINED AND REPLACED, FUEL INJECTION CLEANING, AND DECARBONIZING AND THROTTLE BODY CLEANING. CHECK ENGINE LIGHT WENT AWAY, BUT TURNED BACK ON A FEW DAYS LATER. AGAIN TOOK IT TO DEALER BUT THEY WERE UNABLE TO GET IT TO TURN ON AFTER I LEFT IT, SO RETURNED THE CAR TO ME, NO CHARGE. I HAD ONLY ADDED 87 OCTANE GASOLINE (PER OWNER'S MANUAL RECOMMENDATION) TO MY CAR 3 TIMES PRIOR TO THE FIRST CHECK ENGINE LIGHT EPISODE, AT STATIONS THAT DID NOT SELL E85. DURING SUBSEQUENT CONVERSATION WITH HYUNDAI REP, WAS TOLD MAYBE WATER WAS IN GAS. BUT ENGINE RAN FINE AND I DROVE 100 MILES AFTER LAST GAS FILLUP SO I SUSPECT THERE MAY BE A PROBLEM WITH THE EMISSIONS SENSOR THAT MANIFESTS AS CHECK ENGINE LIGHT WITH RANDOM (INACCURATE) DIAGNOSTIC CODE. I GOT THIS CAR IN CHICAGO, BUT ILLINOIS IS NOT A LOW EMISSIONS VEHICLE STATE, SO THE PLUG-IN HYBRID IS NOT ALLOCATED TO HYUNDAI DEALERS IN ILLINOIS. THE SONATA HYBRID, HOWEVER, IS SOLD HERE BUT I DON'T KNOW IF IT SHARES THE SAME ENGINE/EMISSIONS SENSING SYSTEM AS MY PLUG-IN HYBRID ELECTRIC. DEALER SERVICE DID CHECK FOR OBVIOUS THINGS: GAS CAP, RESETTING THE ENGINE DIAGNOSTIC CHIP. I UNDERSTAND THE 2016 MODEL PHEV IS SUBSTANTIALLY THE SAME AS MY 2017 MODEL, IN CASE SIMILAR CHECK ENGINE LIGHT ISSUE HAPPENED WITH 2016 CARS.