5,119 of the
22,302 complaints filed about the Hyundai Sonata
are about the engine —
100% of everything owners reported.
The worst model year for it is 2011.
The contact owns a 2014 Hyundai Sonata. While the contact's wife was driving 65 MPH, the engine seized. The vehicle rolled to the shoulder of the road. The driver attempted to restart the vehicle, and the vehicle started. The contact stated that the accelerator pedal was depressed; however, the vehicle failed to accelerate. The vehicle failed to accelerate above 25 MPH, and the engine shuttered. The vehicle was driven to the shoulder of the roadway. The vehicle was towed to the residence. The dealer was contacted by phone and made aware of the failure. The vehicle was towed to the dealer. The dealer requested that the contact provide a fleet email associated with the VIN from Enterprise, which was the previous vehicle owner. The manufacturer was contacted by phone but provided no assistance. The failure mileage was 141,000.
NHTSA complaint #11763730 — an unverified report by a vehicle owner.
After receiving the Hyundai Service Campaign 9C2 update on my 2015 Hyundai Sonata on XXX, I have started having jerky acceleration when the car is first started and am driving. Also, while driving at highway speed (~65 mph)) and I take my foot off the accelerator to coast, the engine RPM drops suddenly, anywhere from 250 rpm to 750 rpm, then recovers abruptly to where it was at prior to the drop (typically around 2000 rpm). The engine rpm also drops while driving at slower speeds and recovers but is not as noticeable as it is at highway speeds. It was not doing this prior to the Service Campaign. There are no check engine lights or pending codes. I brought it back to the Hyundai dealer and discussed the issue with them on XXX. They acknowledged it was likely due to the Service Campaign and they did not want to keep the car to look at it and said no damage was being done and it was safe to drive. They said a fix was in the works but did not know how long until it was released and I should receive information in the mail on it. Video link [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA complaint #11763571 — an unverified report by a vehicle owner.
In March 2026 Hyundai did an emissions update Campaign 9C2. Since that update my 2015 Hyundai Sonata SE has run rough and shifted hard. Hyundai stopped doing the update in May 2026. Hyundai has not provided any update to fix the problem they created. I am worried the update is damaging the motor and transmission of a car that was running just fine prior to the update.
NHTSA complaint #11763289 — an unverified report by a vehicle owner.
The contact owns a 2019 Hyundai Sonata. The contact stated that while driving 55 MPH, the check engine warning light illuminated, and the vehicle went into LIMP Mode. The contact stated that the vehicle failed to accelerate above 58 MPH. The contact retrieved DTC: P1326 (Knock Sensor Detection System) at O'Reilly Auto Parts and stated that the knock sensor had previously been replaced. The failure mileage was approximately 90,000.
NHTSA complaint #11763290 — an unverified report by a vehicle owner.
On September 8, 2026, while driving a 2013 Hyundai Sonata Limited at highway speed, the check-engine light began flashing and the vehicle suddenly lost power. The vehicle slowed to approximately 40 mph, then approximately 20 mph, before the engine completely shut off. I had to maneuver the vehicle to the side of the highway while surrounding traffic continued traveling at highway speeds. This created a serious risk of a rear-end collision or other accident. The engine would not operate afterward and appears to have seized. The vehicle had approximately 100,000 miles at the time of the incident. There had been no clear warning of an imminent engine failure before the check-engine light began flashing and the vehicle lost power. The vehicle has not yet received a complete diagnostic inspection, so the precise cause of the failure is currently unknown. The vehicle is available for inspection upon request. No crash, fire, or injuries occurred, but the sudden and severe loss of power created an immediate safety hazard.
NHTSA complaint #11762781 — an unverified report by a vehicle owner.
I am reporting a serious engine failure involving my 2013 Hyundai Sonata. The vehicle's engine was previously inspected by a Hyundai dealership as part of a Hyundai engine recall. I followed Hyundai's instructions and brought the vehicle to the dealership for the required inspection. I was informed that the engine passed the inspection, and an orange marking was placed on the oil dipstick. The Hyundai dealership should have the service record documenting this recall inspection. Many years later, at approximately 120,000 miles, the same engine suddenly failed without warning and became locked/seized. A mechanic attempted to turn the engine and determined that it would not turn. I understand that many years had passed and the vehicle had accumulated additional mileage since the recall inspection. I am not claiming that the previous recall issue necessarily caused the current failure. However, I believe the circumstances warrant investigation because this is the same engine that had previously been inspected under a Hyundai engine recall and determined to have passed the inspection. The vehicle had been routinely maintained. Much of the routine maintenance was performed outside Hyundai dealerships by a mechanic in my family and by me, so the Hyundai dealership service history may not contain all maintenance records. I am concerned that the sudden engine seizure may represent a safety-related engine defect or may potentially be related to the previously recalled engine condition. An unexpected engine seizure can result in a sudden loss of propulsion and create a significant safety risk if it occurs while the vehicle is being driven. I am requesting that NHTSA review this complaint, including the vehicle's recall history and any related complaints or investigations involving the 2013 Hyundai Sonata, and determine whether this failure warrants further investigation. The Hyundai dealership that performed the recall inspection have documentation of that inspection.
NHTSA complaint #11762394 — an unverified report by a vehicle owner.
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.
NHTSA complaint #11762255 — an unverified report by a vehicle owner.
I was driving down the road going the speed limit and all of a sudden it felt like I hit a brick wall my car staked out and I was stuck in the middle of the road for about 20 minutes and finally I got it to start and drove home it did it again 2 months later
NHTSA complaint #11762026 — an unverified report by a vehicle owner.
The contact owns a 2013 Hyundai Sonata. The contact stated that while driving 40 MPH, the vehicle suddenly lost power. The contact was able to coast to the side of the road and turned off the vehicle. The vehicle was unable to restart on the side of the road. The vehicle was towed to a certified mechanic who diagnosed that the engine had seized and needed to be replaced. The vehicle was then towed to the dealer, who confirmed the diagnosis. The dealer asked the contact to provide receipts of past oil changes. After submitting the information to the manufacturer, the request to cover the repair was denied. The vehicle remained with the dealer for a month. The manufacturer was informed of the failure by the dealer. The failure mileage was 52,973.
NHTSA complaint #11761893 — an unverified report by a vehicle owner.
The A/C evaporator core and the core seal needs replacing on 2020 Hyundai Sonata. Car is 6 years old. I already have a confirmed diagnosis with a PPM refrigerant leak tester at the condensate drain line The diagnosis is 100% confirmed. The evaporator is leaking heavily—we pulled 274 PPM at the drain tube and 177 PPM inside the cabin behind the glove box so refrigerent has been leaking out of the vents. My wife and I were getting headaches for no reason. Our AC has failed and this problem was discovered as the issue and I am paying out of pocket to fix something that should not have failed and has leaked out refrigerent.
NHTSA complaint #11761990 — an unverified report by a vehicle owner.
The engine failed due to the known recall defect, dealer confirmed loss of compression in cylinders 2 & 4. I am a federal employee stationed overseas on official duty orders, and Hyundai Motor America is delaying safety recall remedies and buyback negotiations since June 9th.
NHTSA complaint #11761235 — an unverified report by a vehicle owner.
I had taken my Sonata to Mike Miller Hyndia in Peoria,I'll and they agreed to do the recall although they had my vehicle for two weeks. They did not service it and when I picked it up they said I had to drive it till the service engine light come on. I was driving it five days later and heard a loud noise and car started malfunctioning I was stuck in a middle of a intersection and I had to push vehicle off road. I broke my right hand in this process and I have also lost my job I am very concerned why they did not service it after they agreed too and sent me off in it in that condition ..The car is currently parked and unsure what to do with it ..
NHTSA complaint #11760651 — an unverified report by a vehicle owner.
Engine locked up, crank bearing failure, found out there is known failures with this problem and Hyundai had a class action suit against them in the past and issued lifetime warranty for this engine due to this problem. Took car to local dealer, Clay Cooley in Sherman TX, they have been great but Hyundai corporate has denied the claim stating lack of maintenance records. Car has 175,000 miles on it, I have only owned it for about 5-6,000 miles. I have changed the oil in it twice myself I was able to prove one of those with a receipt but I don't have the other receipt and have been unable to get it. The dealer has records of oil changes up to 150k miles then I was able to find additional proof of other oil changes through car fax at smaller lube shops. The previous owner before me changed their own oil also and did not keep receipts I reached out to them with no luck. Ultimately there is only about a 10k mile gap of unprovable maintenance, this engine model has a known issue, it did not make it to 175k miles without proper maintenance, I can't control what previous owners did with their receipts but lifetime warranty should be lifetime not only if you can prove every detail from people you can't control.
NHTSA complaint #11759964 — an unverified report by a vehicle owner.
I was on [XXX] . I was going 70 mph and then my car just instantly stopped accelerating. The check engine started flashing and I pulled to the side. There was a knocking noise and I just stopped. I called my son to come and get us and then my uncle told it to my house. I have several friends that work on cars and have a a tester. Of course they tested it in that same code came up as if it was the knocking center, so I had another friend come and tested with a different tester with the knocking sensor out his own cylinder three it’s not the knocking center the bearing in the motor is on cylinder two, which that’s what it is. I put my pen. I I put my pin number on the website and it’s showing that my car is affected. No it’s not showing on y’all‘s recall because it’s not something that you’re gonna recall. I have a history of my car motor being fixed every six years if I need to provide that, I will email that I’ve been given the runaround to get my car fixed because it’s not showing up on y’all recall, but it is a recall for the bearing in the motor we could’ve gotten hurt no warning no nothing. I just want to be done right because I’ve had my car service for the last six years and nothing went wrong. I just want y’all to be fair and do right and put that on y’all’s recall, I would hate to take this further but if I have to, I will sincerely [XXX]. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA complaint #11759571 — an unverified report by a vehicle owner.
Component & Inspection: Vehicle engine suffered connecting rod bearing failure and entered restricted P1326 "Limp Home Mode" (max 2,000 RPM). The vehicle is grounded and available for inspection at Bud Clary Hyundai in [XXX].Safety Risk: Sudden, unexpected loss of power occurred while driving, placing me and other drivers at immediate risk on public roads due to the vehicle's inability to maintain normal traffic speed or safely accelerate.Dealer & Corporate Confirmation: Active P1326 engine code is confirmed. Car has been held for 14 days. The franchise is violating federal settlement rules by explicitly refusing to execute the mandatory, free mechanical Bearing Clearance Test (BCT) unless I pay out-of-pocket fees.Inspection & Corporate Compliance Failure: Car was brought to the dealer on XXX. The service manager admitted in writing that they are withholding safety diagnostics to protect shop labor hours due to an automated computer flag regarding a clerical title brand discrepancy. Hyundai Corporate is actively enabling this violation; my case manager refuses to issue a manual compliance override for the safety test and is violating federal settlement terms by withholding my contractually mandated alternative transportation.Warning Lamps & Symptoms: Flashing Check Engine Light and limp home mode triggered instantly and unexpectedly on XXX. There were zero warning symptoms, messages, or abnormal noises prior to that date INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA complaint #11759428 — an unverified report by a vehicle owner.
Since I had Service Campaign 9C2 completed, the car hesitates to start, does a mini-lurch upon cold start and runs rough. Two weeks ago, it was put in park, lurched backwards, then died. The starter and battery have been replaced but this has not helped. The car ran fine before this update was done.
NHTSA complaint #11759477 — an unverified report by a vehicle owner.
I bought this car new in 2015, when I was at 97000 miles they had to replace the motor and turbo, I am now at 155844 and they are telling me that basically all 4 cylinders have low compression, cylinder 3 is the worst. They are telling me that this car has to have a new motor. I have not done anything to this vehicle to cause no compression. They want me to pay around 8800.00 to get this fixed.
NHTSA complaint #11759071 — an unverified report by a vehicle owner.