The contact owns a 2011 Hyundai Sonata. The contact stated that while driving approximately 35-40 MPH, the vehicle lost motive power and stalled. The vehicle was towed to a certified mechanic who diagnosed that cylinder #4 had failed causing the engine to seize. The engine was replaced with a used engine. The engine was replaced at approximately 109,000 miles. The contact stated that while driving for approximately 45 minutes, the contact noticed that the vehicle would not exceed 60 MPH. The check engine warning light started flashing. The contact continued to drive the vehicle to a rest stop. After being parked for a while and then restarting the vehicle, several unknown warning lights illuminated. The vehicle then failed to exceed 45 MPH. The vehicle was towed to the dealer to be diagnosed. The contact was informed that the engine had seized due to a lack of engine oil. The contact stated that the engine oil had been changed approximately 2 weeks prior to the failure. The vehicle had not been repaired. The manufacturer was made aware of the failure. The approximate failure mileage was 89,000.

- Oak Lawn, IL, USA

The contact owns a 2011 Hyundai Sonata. The contact stated while driving approximately 35 MPH, the vehicle inadvertently lost motive power and stalled. The contact stated there was a piston failure in the engine allowing oil to leak onto the ground. There were no warning lights illuminated. The vehicle was towed to the local dealer but was not diagnosed. The vehicle was not repaired. The manufacturer was notified of the failure. The VIN was not included in NHTSA Campaign Number: 17V226000 (Engine and Engine Cooling). The approximate failure mileage was 150,000. The VIN was invalid.

- San Jose, CA, USA

We have refill engine oil weekly. After every oil change a month the oil is dark and a needs a quart more to refill. This is regularly since 2015. We purchased the car in 2012. 2019 the front ball joints started clumping in reverse, replaced in 2021. While driving on the freeway and exiting off onto a ramp the car dramatically down shifted and was unable to correct itself. Later discovered the computer module needed replacement. We still are refilling oil weekly. Not to mention replacing the clock spring twice.

- San Tan Valley Az , AZ, USA

2011 Hyundai Sonata. Consumer writes in regards to NHTSA safety recall 15V-568. The consumer requested to be included in the recall, as the vehicle has experienced the same failure. There was metallic debris in the engine crankshaft. This caused the rod bearings to be restricted of oil flow and caused my rod bearings to be damaged. The engine failed.

- Jacksonville, FL, USA

2011 Hyundai Sonata. Consumer writes in regards to muffler noises, fuse outlet replacement, loose window handle and engine replacement repair issues. The consumer was informed the baffles in the muffler were coming apart. Also, the vehicle suddenly stalled while in the midst of driving and it would not re-start. The vehicle had to be towed to the dealer. The dealer stated the engine needed to be replaced. However, it would have to be taken apart to see what caused it to happen. The dealer informed the consumer the connecting rods were bad and a recall had been issue on the engine due to concerns of metal debris entering the engine compartment causing the connecting rods to fail. The engine was replaced. However, when the consumer went to retrieve the vehicle, the other problems were not fixed. When the consumer drove off the lot, the vehicle began to shake violently and the check engine light illuminated. The dealer informed the consumer the engine they put in was bad, and it would be months before they could get another one.

- San Jose, CA, USA

The car randomly stalled at traffic lights for about ten times now throughout my 3.5 years' ownership. I bought my car in March 2010. Within one month, the engine stalled when braking to a full stop at traffic light. The dealer couldn't reproduce the problem. One month later, my car cut off again while sitting at traffic light. Another one or two months later, it happened the third time. The dealer kept my towed car for two weeks but had no clue. From then on, I just gave up. One day, when it sat at traffic light, the car shook a little like someone hit me. The other day, this hit-like shake happened again while at traffic light. This time, the car even shook several times during driving after leaving that traffic light, with the check engine light blinking in accordance with the shake. On the following day, my car finally stalled again at a traffic light. Except the first one, all other occurrences happened while the car sat at traffic light and I stepped on the brake pedal. After I restarted the car, it could run smoothly for at least one month. Given the occurrence frequency, the chance to reproduce the problem at dealership is almost zero. And they refused to lend me their computer that I could hook up to the car to record driving data. I had also contacted Hyundai customer affairs. All they can do was just send me to the dealer and close the ticket. Recently, the car stalled again during a low-speed driving. The car lost driving power completely with check engine light on. I was completely shocked and hurriedly stepped the brake, switched the gear to park, and restarted the car. Fortunately, no car was around. This is really terrifying and I am really disappointed and embarrassed.

- Mc Lean, VA, USA

There is a smell of gas/engine fumes notable in the vehicle on occasion. The problem does not happen consistently, however there are some common factors to when the smell in noticeable. These factors include: 1) the engine must be hot, generally having been driven for at least 15 minutes or more. The smell is never noticeable when the engine is cold, such as after sitting overnight. 2) the vehicle must be either moving at very slow speeds of <25 M.P.H., or sitting still. Examples would include driving through parking lots, sitting at an idle for a long period at a stop light, when first starting the vehicle after sitting in a parking lot for awhile, etc. 3) when the gas / fume smell is notable with greatest intensity, it seems to occur after a hot engine soak of 15~45 minutes at ambient temperatures of 30 degrees Fahrenheit or above and in conditions of moderate- to high-humidity. Examples include during periods of heavy fog, rainy days, snowstorms, etc. On occasion, the smell is strong enough that it is no longer comfortable to remain in the vehicle. Rolling down a window at speeds >25 M.P.H. to clear out the cabin air, followed by activating the HVAC recirculation button will lessens immediate recurrence the smell to some extent. Finding ways to "mask" the smell are of lesser concern than determining why the smell exists in the first place. The vehicle has been in for this concern twice, with neither trip to the service bay having resolved the concern. While it does not appear to be an issue causing immediate danger (no noticeable fuel leaks or signs of fire), the smell of gas and engine fumes entering the passenger cabin is a bit concerning, both from a potential fire hazard in the future, and/or exposure to carbon dioxide and other noxious fumes while operating the vehicle. I will return the vehicle for a third visit to resolve this concern.

- Rochester Hills, MI, USA

The contact owns a 2011 Hyundai Sonata. The contact stated that the check engine warning light was illuminated. The vehicle was towed to the dealer for diagnostics, which located the failure at the engine. The engine oil experienced a block that caused the oil not to circulate and the engine to fail. The engine would need to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure. The VIN was not available. The failure and the current mileage was 30,000.

- Middletown, OH, USA

The 2011 Sonata is unable to start by pressing down on both the brake pedal and start button. I had this problem for over 3 months. This failure happens about 1-2 times a week. Once failed to start, the brake pedal locked up while the dashboard display still says "press down brake pedal to start." With repeated tries to start the car, it sometimes started after 5-10 minutes, but sometimes it took over 1 hours to start the engine. Hyundai dealership said they cannot help because the problem cannot be reproduced when they service the car. It is a rather new car but very unreliable.

- San Diego, CA, USA

After having 3 of 5 recall fixes performed, battery charging system warning light and sounds activated. Car lost power at low revs. Required giving full throttle to enable gas engine to kick in and gain enough speed to safely stay with traffic. After pulling over and turning engine off/on, problem seemed to resolve itself. Happened again in highway traffic while entering exit ramp resulting in a dangerous loss of power. Returned vehicle to dealership for repair. Dealership assured me that they knew what the issue was and that it would be repaired. 2 days later issue happened 3 times. Each time on the highway at approx. 65mph with nowhere safe to conveniently pull over.

- Stroudsburg, PA, USA

This is on the hybrid Sonata. Twice in 2 weeks, I am driving down a highway, I felt a jerk in the car, the ready light flashes and the wrench symbol shows up. The car is on battery power only. I coast on battery till I can pull into a parking lot. Shut the car off. Luckily both times it started back up. Bob king Hyundai in winston-salem says they don't know why it would do that. We are waiting on some parts that are updates, but don't know if that will fix the shut down issue.

- Walkertown, NC, USA

The contact owns a 2011 Hyundai Sonata. The contact stated that after driving the vehicle for extended periods of time, occupants would become fatigued, light headed, and experienced headaches. The contact also stated that she nearly passed out on one occasion. The contact took the vehicle to a fire department to have it tested for carbon monoxide and the test came back negative. The fireman that tested the vehicle also reported that he became light headed and experienced a headache while driving it. The contact spoke with the manufacturer and was informed that there was nothing that could be done because the dealer stated that there were no carbon monoxide leaks. The failure mileage and current mileage was unknown. The VIN was unknown.

- Abbottstown, PA, USA

While driving on the freeway I experienced a large jolt which resulted in an unexpected shift in the transmission gear where my speed of approx. 65 mph at 2000 RPM dropped to 45 mph at approx 3800 RPM. Had the freeway traffic not been light at the time, this could have caused an accident. Although the transmission indicator showed it was in "D", the gear was probably closer to 2nd gear. I pulled off the freeway and shifted from D to R to N to P, however it seemed that it was locked in 2nd gear. I managed to drive it in that gear to the local Hyundai dealer. However once the engine was shutoff and restarted, the transmission was back in its normal gear and they were not able to duplicate that event. In addition, according to the service representative, the computer showed no problems. After doing a search on the internet, it appears this has happened to others.

- Hawthorne, CA, USA

On the way to work this morning, my Sonata hybrid started beeping and "check charging system" appeared on the dashboard. My car suddenly started losing engine power to the point where my car would not move after the stop light turned green, leaving me stuck in the middle of a huge intersection with people almost hitting me. After restarting my car, it finally started to move, but repeated the same instance at the next stop light. This is a serious safety issue. I had to have my car towed to the dealership because I was not going to risk my safety and life. People need to be aware of this issue because if other vehicles are experiencing the same problem, someone could get into a serious car wreck which could be potentially fatal, if happened on a freeway.

- Palm Beach Gardens, FL, USA

Power to the engine completely cut out while driving. All warning lights illuminated and a large warning message appeared: Check charging system. I coasted to the highway shoulder. The electrical system was providing power to the accessories only (radio, air) but it was stuck in this mode. Would not turn off until I depressed the start/stop button for approx 5 seconds. Eventually the car powered on again. This happened twice in the last 48 hours. The car is currently at the dealer. Reading through NHTSA reports, it appears this has happened to other Sonata hybrid customers. It seems there is a very dangerous problem that causes the engine to turn off while driving.

- San Jose, CA, USA

Hyundai Sonata hybrid. First problem occurred at approximately 6400 miles. I was driving between 60-65 mph on the freeway. Vehicle lost power and alarm sounded. "check chargin system" light illuminated and the car lost all power to drive, gas engine and hybrid engine shut-off in middle of freeway. Was able to make it off freeway. Let car come to rest and restarted car. Everything seemed normal, drove in parking lot and was close to home. Taking to dealership who has not heard of issue.

- Houston, TX, USA

I drive the Hyundai Sonata hybrid. The first time the problem occurred at approx 9800 miles, I was driving 60 mph on a highway when the vehicle lost battery power and an alarm sounded, and then a signal indicating to "check charging system." I immediately took the vehicle to my Hyundai dealership where they were aware of the issue, but did not know how to fix it and suggested I just simply turn off and then restart my car. It happened two additional times, one while approaching a stop light, and another time while I was stopped at a stop light. The last time it happened, I could not get my vehicle to reset by restarting once. I had to shut the vehicle off, then attempted several times to restart. The 4th time I tried to start it, I was able to do so sucessfully. I did notice the last time it happened, the engine light remained on even after battery power was restored. I am taking it back to the dealership tomorrow and demanding a solution. This is just too dangerous to lose power in high-speed traffic, and the problem seems to be occuring at all speeds.

- Canyon Lake, TX, USA

The contact owns a 2011 Hyundai Sonata. The contact stated while driving 20 mph the vehicle stalled. The vehicle would not restart. The vehicle was towed to an authorized dealer and the contact was informed that the fuel pump failed. The fuel pump was replaced, but the failure continued. The vehicle was taken back to the dealer who was in the process of diagnosing the failure. The manufacturer was not made aware of the failure. The failure mileage was 8,500.

- Mililani, HI, USA

2011 Hyundai Sonata hybrid stops loses power comes to complete stop - for the third time in two months when I started my car the service indicator light came on and stayed on. I noticed this time that the car would not go faster than 40 mph and the engine is not running the car appears to be running just off the electric motor and the battery. The car went for about 2 miles and the car lost power and came to complete stop. I had to completely shut off the car and restart it before it would move again - this is a re-occurring and very dangerous situation.

- Las Vegas, NV, USA

At 5:15 pm on 8/22/11, I got into my car to go work and it would not start. It was very hot and I was sweating trying to get the car started. I tried several times but the car would not start. I called the dealership and I got no assistance. The screen on the dash-board read "press the brakes" which I did like I have done in the past. I gave up and contacted a friend to take me to work. Later, that night it did start but would not start again so I assumed it was the battery. I called roadside service and they arrived 5:30 am in the morning to jump start the car (not the battery). It gets better, a lady that lives in my area was walking her dog, who has a black Sonata 2011 told me that her Sonata would not start and she just got her vehicle back. She told me what was wrong with my car. I called the dealership again while I was waiting on a tow truck and explained how this could have been a bad situation if I was stranded with my mother in the car who just had surgery to remove cancer. I explained that I needed my car repaired immediately because I needed to Transport my mother and I was concern the car would stop working again. The Hyundai representative stated he would have it fixed in 15 minutes and he also indicated that there has been a few Sonatas that the "sensor" under the brake pedal has gone bad. The salesperson that sold the vehicle to me stated the same that the "sensor" goes bad. Eight (8) months of ownership and the lady with the black Sonata had her car less. The tow truck driver said he has picked up a couple of Sonatas that would not start.

- Tuscaloosa, AL, USA