I was traveling down a highway when my engine started to make a knocking sound. The check engine light came on, and within 10 seconds my car stopped running. I was still moving when this happened. I was fortunate to be able to coast to a close by side road. I am gravely concerned that this could have happened on the interstate at higher speeds, and the potential consequences of such. I had the car towed to a dealer, and they tell me the engine is shot. I contacted Hyundai customer care, and their response was "what do you want me to do about it." After more research, I have found numerous other instances of this engine failure. If this is an ongoing problem, I feel Hyundai should do something before someone gets killed when this happens. Please note I am the second owner of this car. The mileage at just over 85,000 is mainly highway miles, and the car is serviced regularly.

- Etowah , TN, USA

Oil light blinked on and off twice. Car was making a knocking noise. Stopped to check oil; absolutely no oil in the vehicle. No sign of leak; no smoking; no other indication of problem. Put 3 quarts of oil in the car. Knocking sound was worse. Drove car home and haven't driven it since. This is one of many problems I've had with this car. I get regular oil changes. I haven't had the car looked at yet due to cost and out of warranty. I've read other complaints of loss of oil resulting in complete engine failure. There was absolutely no indication that the oil was even low which I attribute to the faulty electrical system since I've had problems with that as well. It's my opinion that this car is unsafe to drive. I've read this year model has over 900 problems while other year models have average of 230 something problems. Obviously, this car should be completely recalled and replaced by Hyundai dealer.

- Vinton, LA, USA

Tell us what happened: Bought vehicle new and regularly had serviced by dealer. Vehicle died without any warning coming off highway and I had to turn flashers on and place in park to restart. Engine started knocking with no warning and no warning lights illuminated. Had towed to dealer and was told engine had no oil and requires an engine change. Where did it go? there has never been any signs of smoke, burning smell or leaks anywhere and no warning lights ever giving indication of a low oil or low oil pressure indication nor any other engine light warning. Now dealer says we have to convince regional manager that this was not neglect on our part to have covered under the 100,000 mile power-train warranty.

- Honolulu , HI, USA

I am a loyal Hyundai customer who has owned 4 of their vehicles. I took my car in to superior Hyundai North to have a couple safety recall items taken care of. I also would hear a wind type sound sometimes (within a week prior to taking it in) when I would start driving from a stopped position. When I called the dealership service dept. They told me they had bad news. My engine had to be replaced. They said there was no oil in it. I asked them how it could be empty as my car has never leaked, never smoked, never smelled like oil burning, had only approx. 48,000 miles on it, and had been serviced. They had to take some of the engine apart and said since they found no sludge in the engine, it was covered under the warranty. Problem I have is they are replacing my engine with a rebuilt one. They said Hyundai won't approve them to put a new engine in it. I have no way of finding out what happened to the rebuilt engine they are putting in my car and they can't tell me how many miles was on it originally. They told me there was one more car like mine there with the exact same problem. They also tried to tell me it wouldn't hurt my trade-in value. That I didn't have to disclose the engine replacement. One, that's not a moral and deceitful problem that I would never do and two, I believe it's the law that I would have to disclose it. I spoke to one of the salesmen about buying the loaner car I'm driving with the trade of my car and the first thing he told me was the problem with my engine would cause the trade-in value to be less. Hmmm...just as I thought!! they need to either put a new engine in my car or give me the top value of my car with a good discount and price on a new one or they will lose a very loyal customer!

- Hamilton, OH, USA

While driving in the fast lane of a 3 lane freeway on a steep upgrade, the car suddenly and without warning lost a huge amount of engine power. The effect was similar to no longer pushing the accelerator pedal. This caused the cars in back of me to slam on their brakes as well as scaring me as I had no idea what happened. This has occurred twice so far. Hyundai America (ha) is well aware of the problem and from what I have discovered after viewing ha forums, this problem is specific to the Sonata's with the 2.0 turbocharged engines including model years 2011 - 2014. Not only is the problem a result of a poorly designed waste gate control rod, it is a huge safety issue. Inexperienced drivers as well as experienced drivers are going to be harmed. Ha is well aware of the problem and has decided not to cover the repair expense after 60,000 miles. Apparently, a functioning turbocharger is not part of the engine! please insure the ha not only fixes this safety hazard but also reimburses owners for previously charged repair expense. My car was repaired around 56,000 miles andat 67,000 miles, the problem is back. Thank you

- Carson City, NV, USA

While driving the car on interstate 95, the car abruptly stalled out doing 60 mpg, the flashers would not work. I shifted it in neutral and it started after two attempts. We proceeded to get off the interstate onto another four lane highway. About a half a mile down the road, it stalled again. After two more attempts to restart the engine, it did restart and everything seemed fine. Three more miles down the road, the car stalled out again and then started smoking. We could not restart the car and the flashers initially would not work again. After ten seconds, the flashers started to work and then we proceeded to push the car across the highway into a 7-11. The engine had seized up. The car had to be towed to the Hyundai dealer. After calling the dealer the next day, I found out that four cars with the same problem were waiting to be repaired. The dealer is now putting a new engine in the car since it is still under warranty. The problem is they are putting a new engine in the car with the same exact problem. They have not fixed the initial problem. I am afraid this same exact incident will happen again and I will not be as lucky. They are putting my life and my families' life in jeopardy. I want them to buy back the car, this should not happen with only 25,000 miles on the car and an up-to-date car service record.

- Brookhaven, PA, USA

In the span 2 months, there were 2 occasions where my car would not start. I thought it was the battery and had someone jump me and it still wouldn't start. However, after trying several times, car would finally start. One other time I pulled into a store and when I came out, my car wouldn't start. After several attempts, it finally started. Then on November 28th, 2014, my boyfriend was driving my car and it just stopped running. I had it towed to an independent mechanic and they stated that the engine had seized. I did not have any warning or indication that anything was wrong. Today I have to have it towed to the Hyundai dealership and they will let me know the exact problem and if it is covered under the warranty.

- Moon Township, PA, USA

Engine seized.

- Akron, OH, USA

As I began driving my 2011 Hyundai Sonata that morning I heard a rattle whenever my RPM would reach between 2-3K. I contacted my local Hyundai dealership and made an appointment. Today 11/20/14I was told that my engine needed to be replaced. My car was previously in the dealership late September 2014for an oil change and also due to a small knock/bang as I accelerated. The technician found the knock to be a support hitting against the firewall. Upon tightening said support the problem went away. The car was reportedly teat driven by the technician numerous times to conclude that the problem was fixed. Oil change was done as usual and my car was given a clean bill of health (only a recommendation of brakes getting low).

- Chicopee, MA, USA

Car started making knocking noises while driving up hill, losing power. Proceeded to drive it home. Checked oil and appeared completely dry. No engine warning lights came on when car had previously been driven. No oil leaks seen. Added oil and then drove to dealership, where they stated engine needed to be replaced. Regularly serviced car with oil changes, 120K miles with almost all freeway commute.

- Carlsbad, CA, USA

The contact owns a 2011 Hyundai Sonata. While driving approximately 45 mph, the vehicle stalled without warning. The vehicle was towed to the independent mechanic, who diagnosed that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was not notified of the failure. The approximate failure mileage was 74,000.

- Plano , TX, USA

In May 2014, while driving at about 40 mph, maybe 1200 RPM, my engine suddenly accelerated to 4500-5000 RPM, without a simultaneous rise in speed. A week or two later, the car did the same, under about the same conditions. The dealer could find no faults or codes, and could not duplicate the occurrence; not surprising since it was sporadic. The problem continued, with considerably more frequency; almost daily. Again I took it to the dealer in late July (mccafferty Hyundai, langhorne, pa), and while a technician was driving with me, the engine raced again. They told me that there was a tech bulletin on this problem, and they would repair the car. The problem was in a module and needed recoding. At least that's what I thought they said. That repair seemed to cure the problem, until September, when a single occurrence happened. I though this was maybe a fluke, but the problem happened several more times in the following weeks. Today, 11/4/14, after several days in the dealer's shop, an insurance service tech said he could find no problem. I am now afraid to drive this car. While the car does not accelerate, maybe it's just a matter of time when the racing engine will cause severe acceleration and a subsequent accident.

- Florence, NJ, USA

The contact owns a 2011 Hyundai Sonata. The contact stated that while making a turn, the vehicle stalled without warning. The vehicle was taken to a dealer where it was repaired under NHTSA campaign number: 10V426000 (steering) but the failure recurred. The manufacturer was notified of the failure. The failure mileage was 67,000.

- Spring, TX, USA

My 2011 Hyundai Sonata like many of the other complaints on here has had catastrophic engine failure due to a snapped rod. Like many of you I have kept up with the regular maintenance schedule and have been shut down by Hyundai for repair under the 100,000 mile warranty. This problem is a serious public safety concern as it happens while the car is in motion and my question is what will it take for the NHTSA to take action and fully investigate this issue and bring it to recall? with the amount of complaints listed on the NHTSA website for this exact issue it seems like they are waiting for injury or even worse to occur before this issue is taken seriously.

- Albuquerque, NM, USA

10/1/2014 @ 7:30pm est - while driving home, was at a red light when the car stalled out. Then a loud knocking sound happened. Engine light was on* it is very unsafe for the engine to stall or just randomly shutoff while in traffic. There were no signs or warnings, the vehicle just stalled. Vehicle was not safe to operate. I had the vehicle towed to northtowne Hyundai dealer on sheridan drive, buffalo NY.10/3/2014 @ 2:47pm est - northtowne Hyundai dealer called me said that I need to replace my engine because the piston popped. I said well, my car is well within the warranty, isn't this covered? northtowne Hyundai dealer said that we can't submit your warranty claim with out receipts of your maintenance from 5K miles to present. 10/3 - 10/13/2014 - contacted our 3 local places we like to send our vehicles to for copies of our receipts. With no problem we were able to obtain copies of our last 7 oil changes and general maintenance receipts. 10/14/2014 @ 2:00pm est - my husband gave northtowne Hyundai dealer our receipts and he stated that he will submit our claim to Hyundai. 10/24/2014 @ 8:59am est - "regional" / "corporate" called me and stated "the district manager who would have authorized the repair, had the dealership partially disassemble the engine; take off the cover for inspection, and there's a condition of sludge which is indicative of either the maintenance intervals not being followed; oil change not frequently enough or possibly the quality or grade of the oil used. In either case these is not a manufacture defect, so he has denied warranty coverage." I've also added my complaint to the following:[ www.chimicles.com/2011-Hyundai-Sonata-engine-failure-class-action-lawsuit ] ** our last oil change was 8/2/2014 at 43K miles ** we had a clean bill of health, no issues were reported or maintenance recommended at that time.

- Buffalo, NY, USA

I was driving down a 4 laneroadway when the engine stopped. I was able to coast into a gas station and noticed a small amount of smoke coming from the engine. Had it towed to a dealership and 2 days later they told me it was a seized engine and that it was only 1/2 quart low. I filed a claim with my extended warranty service. They sent an inspector out and his finding were it was 2-3 quarts low and cited owner neglect. Warranty service denied the claim. I use royal purple synthetic oil and have used this same oil for the past 15 years in all my vehicles. I had my oil changed in July..approximately 3 months prior.

- Spring , TX, USA

While at a red light on highway 45 in whistler Alabama car just cut off and would not crank back up, police had to come and stop traffic and push car out of the highway so it wouldn't be an accident because it was near the interstate exits to highway 45.

- Whistler, AL, USA

I was driving my 2011 Hyundai Sonata on a mountain road 10/4/2014 when it started to make a clicking sound coming from the engine. Before I even had the chance to pull over all of my sensors went of the engine completely died including power brakes and steering. Huge safety concern as I was driving on a winding mountain road. Dealership is telling me I have to replace my engine and because I'm the second owner the 100,000 mile warranty doesn't apply to me. This vehicle needs to be recalled for this huge manufacturing and overly dangerous flaw.

- Albuquerque , NM, USA

I was driving down the highway and the car stalled. I coasted into an empty parking lot and turned it off. When I tried to restart it, I heard one click and then nothing. There was no evidence that anything was wrong, no warning lights, no weird noises, nothing. I had the car towed the following morning and was told by the repair shop that the engine seized up. I faithfully have my oil changed and there was no indication that the oil was low.

- Pemberton, NJ, USA

The contact owns a 2011 Hyundai Sonata. While driving 70 mph, the vehicle stalled and smoke appeared from the front of the vehicle. The vehicle was towed to a dealer, but was not diagnosed or repaired. The manufacturer was not made aware of the failure. The failure mileage was 130,000.

- Middleburg Heights, OH, USA