I purchased a 2019 Hyundai Sonata SE in December 2024. Within one month, the vehicle consumed 3.5 quarts of oil out of a 5-quart capacity. After researching the issue, I discovered that this is a known engine defect covered under Hyundai Technical Service Bulletin 23-EM-008H, which relates to excessive oil consumption. This condition can lead to engine failure, posing a significant safety risk if the engine fails while driving at high speeds or in traffic. This issue is part of an active class-action lawsuit and has affected numerous vehicles with the same engine type. I am reporting this defect so that the NHTSA can track the scope of the problem and determine whether a recall should be issued.

- Maryville, TN, USA

Failed Component: Engine - Burnt Valve/ Snapped Piston/ Piston Scrapping Internally; available for inspection - Risk of safety: Car sputters/jerks upon acceleration, takes a long time to gain speed, STALLS when slowing or stopping, may or not start after stalling, violently shakes while driving - Problem has been confirmed by Hyundai dealer/repair - Component has not been inspected by the manufacturer, police, insurance representative; only Hyundai repair - Warning lamp, messages, and symptom PRIOR to failure, NO, after the failure, YES; check engine light and all symptoms listed above; all appeared approximately September 15, 2024. Since the purchase of the vehicle in January 2024, I have made complaint regarding the performance of the vehicle. Have had multiple oil changes/fill ups within the last 7 months, due to excessive oil consumption. Vehicle has had scheduled maintenance, several diagnostics, and too many trips to the dealership/repair for a 5 year old vehicle, with regular maintenance, and 3 owners. I have owned the vehicle for less than a year and I am UNABLE TO DRIVE IT DUE TO HYUNDAI STATING IT NEEDS A NEW ENGINE. It stalls when slowing and stopping, which it may or may not start back up - this happened a few times in the middle of traffic. It will not gain speed appropriately when moving from a complete stop, inhibiting me from keeping up with traffic. It shakes violently while accelerating, causing mishandling and ability to steer effectively.

- Akron, OH, USA

Car has a rod knock, has been looked at by a private mechanic, seen online there was a recall on Hyundai Sonatas for rod knock issues.

- Easley, SC, USA

Starting in July 2023 I have noticed that the oil consumption for my car is racing through the engine. I barely make it 1000 miles before the oil is completely gone. After 2 local oil changes - I decided to take it to the Hyundai dealer where I purchased the car. This was in October - I have brought my car in 4 times for 1000 mile oil consumption tests. I had to add an additional visit due to the fact that Hyundai changed the testing standards. Now I have to bring it again today - Hyundai has not told me what the next step is other than I have to leave the car there all day - after they speak to tech support they will determine next steps. Most likely a combustion cleaning. Then I have to start the 1000 mile consumption tests again. I live 35 mins from the dealer - I have had to hire someone to take me there to leave car - and I then have to take mass transit to work. There are never any loaners because they are booked months in advance. I have had to rent numerous cars for long distance travel due to the mileage meter of 1000 miles on my car - I am not allowed to go over - if I do have to start all over again. That happened to me the first time. My car is crap at this point - I am not able to use it as I should be able to and Hyundai is giving us the run around. I have been contacted about trading it in and getting a new Hyundai - what a scam. I am not the only person - there are so many of us - follow the chats on Facebook and Reddit - nobody is helping us. The staff said if your engine seizes - that would be great. People are seizing on highways - that is very scary to me. Why is this not recalled yet?

- Point Pleasant Boro, NJ, USA

Car consumes excessive oil -?" one quart about every 500-700 miles. This has caused sludge in the engine and the car hesitates significantly on starting from a stopped position and now hesitates even at highway speeds. This has become a definite safety issue. If the car stalls it is only a matter of time before I am hit by another driver. The dealer first stated the oil consumption was fine IF it was one quart every 1,000 miles and that no repairs would be needed. My car is consuming almost double that amount of oil. Dealership agreed to look at it; stated the car needs a new engine. Hyundai refused to even do an oil consumption test, let alone repair/replace the engine. The -??sludge-?? in the oil that Hyundai states was present is a result of the oil consumption (even the dealer service department verbally agreed). I-??m literally putting new oil in it about once a week! There is no possibility this would NOT cause sludge. In addition, dealership said to expect the engine to fail fairly soon. Hyundai claims the car was not maintained properly; however, that is untrue. I-??ve submitted records to them that I had. The warranty has no requirement that the oil must be changed or maintained by a certain individual or company. Without a new engine, the car will continue to hesitate and will eventually fail. Hesitation (and especially engine failure) subjects me to a much higher possibility of a crash causing injury or death to myself or someone else. Hyunadai should absolutely recall the thousands of vehicles having this exact same issue.

- West Lafayette, IN, USA

The transmission in my vehicle makes a whine when shifting at about 35-40 miles per hour. No other car I ever drove made that noise. Hyundai has replaced the transmission 3 times and they still could not fix it. After the third replacement they said it's normal and that other Sonatas make that noise. That cannot be true. They did not replace the transmission 3 times if that noise is normal. If it IS true and other Sonatas make that noise, there may be a defect that will turn dangerous in other Sonatas. The second time the transmission was replaced, the service manager told me they found metal fragments in the transmission fluid. I don't know what problem this defect will cause later on. If you would like to inspect my car to determine if this is dangerous, I can make it available. Thanks! P.S. - Below, I have to pick a date of the incident and mileage at that time (so I chose when I first reported it to Hyundai), but this happens every time I drive the car.

- Milford, CT, USA