general problems of the 2015 Hyundai Sonata - part 1

The engine light started to come on and go off and when I got the codes ran, it said something along the line of misfire. I had the spark plugs changed and I kept regular maintenance done on oil changes and tune ups. Now my engine is knocking and the vehicle is in limp mode.

My 2015 Hyundai Sonata has demonstrated multiple instances of unintended acceleration and braking failure: April 20, 2024 – while idling in a drive-thru line, the vehicle suddenly lurched forward without any attempt to accelerate and crashed into the vehicle in front of me. I was unable to stop it. This resulted in the other car being totaled. I took it to a Hyundai dealership afterward, but they found no definitive cause. April 4, 2025 – my daughter was driving and attempted to stop at a red light. Despite applying the brakes, the car did not stop and continued through the intersection, striking the door of another vehicle. May 12, 2025 – today, while using cruise control set to 55 mph, the car began accelerating beyond the set speed without input. It appears the cruise control system is malfunctioning and not disengaging as expected. The vehicle currently shows no open recalls, but I found that similar issues were previously investigated under NHTSA action dp21003 for this model year. These incidents occurred months apart, but the behavior is consistent and extremely dangerous. I am requesting a formal investigation. The safety of my family and others on the road is at risk.

My transmission literally went out once on me the second day after I financed it. Now, less than a year later, it says I need to replace the transmission again. This is ridiculous.

The contact owns a 2015 Hyundai Sonata. The contact stated while driving at an undisclosed speed, the accelerator pedal was depressed; however, the vehicle failed to accelerate as intended. In addition, the check engine warning light illuminated, and the vehicle lost motive power. The vehicle was towed to the dealer where it was diagnosed with engine failure. The contact was informed that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure; however, the engine replacement request was denied. The failure mileage was approximately 140,829.

Engine just stopped working. Car stop running turned off in the middle of traffic in dallas TX. I took my car for an oil change the mechanic said he’s had plenty of 2015 Sonata engines just give out and some catch a fire as well. It gave no warning and no smoke. This happened last week.

The contacts daughter owns a 2015 Hyundai Sonata. The contact stated that while the vehicle was idled the vehicle hesitated. The contact stated that his daughter had to depress the accelerator pedal to rev the engine. The contact then stated that on a separate occasion while driving at an undisclosed speed, the vehicle hesitated and stalled. Additionally, the contact stated that on another separate occasion while his daughter was driving at an undisclosed speed, the vehicle unexpectedly accelerated at rapid speed. The contact’s daughter was able to gain control of the vehicle and depressed the brake pedal to stop the vehicle. The check engine warning light was illuminated. The vehicle was towed to an independent mechanic where the vehicle remained, and the diagnoses had not yet been determined. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 95,000.

The engine and yes it is. Because my car turned off in the middle of the loop on the highway when there was a lot of traffic and we could have gotten hit. No it has not been. No it has not been. We were driving on the highway then the engine started sputtering and it wouldn’t go faster then 40 when I tried pulling off to the side that’s when the engine ,battery ,and oil light turned on and after that the car just shut off and wouldn’t want to turn back on.

Can't use eco sport motor is accelerate and the car can't read the sensors a/c stop working brakes hard to press.

I am 86 years old. I bought the car brand new so I am the original owner. I have kept the car perfectly maintained and garaged from the day I bought it. My wife is also 86. She and I are the only ones that drive the car. To date, it has 73,822 miles on it. The main issue I am having is random, unpredictable stalling and hesitation when trying to accelerate. We have also had unintended acceleration. This always happens at the worst times which causes grave concern for our safety. We have taken the care to the dealership here in cape girardeau, mo called chris auffenberg Hyundai. They've charged me $130 only to tell me nothing is wrong. I have continued to try to work with them and they now have decided a new fuel pump will fix this which is $730. I have noticed there are already hundreds of complaints on the 2015 that all say they have the same exact issues I am having but this dealership doesn't seem to care. Here is what I have read. "the most common issue in the 2015 Sonata lies with its faulty throttle control system, which can cause stalling, hesitation, and even unintended acceleration. Currently, there is no fix from Hyundai. " my dealership will not acknowledge this even though it is public information. I feel like they are going to keep replacing parts and are taking advantage of me. Darren pruitt is the service manager at this dealership and I am not happy how he is handling this. Please let me know if there is any additional information I can provide.

My daughter was driving on the interstate when the car went into limp mode and the engine light was flashing. We had it towed to hyundia dealership where they did an engine update. Had it for 3 months when it did the same thing to her again. Had it towed again to same dealership where they are telling me it needs a new engine.

The engine stalls out randomly. This is the third time it's done it. The first time was while I was exiting the freeway on March of 2021, which I thought was a fluke. The second time was July 19th and the third time was July 30th. There were no warning lights or messages. Took it to the dealer and they said that everything came back fine with the engine. They confirmed that the rpms were too high when it was in a parked position and the engine was on when they first took it in. They suggested I replace the starter. I'm going to a different mechanic for a second opinion. The car was in motion with my foot on the gas pedal when it started to stall. There is no way that it is from a starter.

Driving at 55 and the engine blew. No warning, no check engine light, no sign of anything wrong. Power steering loss, limo mode activation. Almost rear ended during catastrophic failure. 111,000 miles.

Major oil consumption going on for years. Took in to dealer two years ago, they know there is a problem. They told me I could spend thousands of dollars to tear it apart to find out what is going on, and also told me to call corporate. I got no where with either, even though they recalled the engine in other Sonata cars, just not our eco model. Slowly started having throttle issues at 4 to 5 year mark. Informed dealer service center that it wasn't moving like it should when gas was pressed. Now, the car is having major problems with acceleration. Barely would go in reverse, drove 1. 5 blocks, speed not matching to throttle, press on gas, barely moving from a stop, going really slow, had to turn around and take back home. Our problem with the car is the same that others are complaining about. The car is not safe for a 7 year old car that started having problems at the 4 to 5 year mark.

I was driving on the expressway. After about 18 miles the vehicle slowly decelerated to a stop. I was able to safely exit the expressway to the side street. I turned the car off for a few minutes. It started back up but has not accelerated pass 20/25 miles. There’s also major oil consumption. Camshaft position & ccv issues yearly requiring sensors to be replaced. Increased gas consumption. There’s also been a humming sound coming from the car that’s not been able to be diagnosed by any mechanics.

The contact owns a 2015 Hyundai Sonata. The contact stated that while driving 40 mph, the vehicle failed to accelerate while the check engine warning light was illuminated. The vehicle was towed to an independent mechanic where it was diagnosed that the throttle control module needed to be replaced. The vehicle was repaired however, two weeks later the check engine warning light illuminated. The vehicle was taken to the dealer where it was diagnosed that the voice coil motor (vcm) needed to be replaced. The vehicle was repaired. The manufacturer was not notified of the failure. The approximate failure mileage was 127,828.

While going home on highway 95 at approximately 70 mph. The vehicle stalled almost causing many accidents. Thank goodness I steered it on the shoulder and it will not restart I had to call for a tow. This was the 3rd time this happened. The first time was approximately a month in 2015 after my purchase it stalled on the highway. Again, in 2017 it once again stalled on the highway while I was driving. The dealership has told me on all 2 previous occasions that they had fixed the problem and it wasn't going to happen again. Here we are in 2022 and it stalled again. Why can't they just replace the engine? this is the second week and my car is still in the dealership which they are saying they don't know what the problem is smh.

My engine light has been on for over one year. I took it to the dealership to see what was going on and to get an oil change. The dealership stated that there could be a variety of issues and that they would turn the light off and when it came back on to bring it back to them. The staff was not the most professional so I opted to not take it back unless there was a significant issue. My car constantly accelerates when I am on the brakes at a light and then when I let off the brakes, the car accelerates before I put my foot on the gas. I recently backed out of my parking space and without my foot on the gas, I bumped into a neighbor's car. There was no damage to their car but my car has a dent in it. Everyone is safe and fine but this could have been way worse if I was in a parking lot or on the road. The car does not accelerate when I put my foot on the gas on the highway either. I have had some close calls getting onto the highway because I can press the pedal to the floor and not get the speed needed to go fast enough. I am making plans to take it back to the dealership and report my dent because this acceleration issue is very annoying when driving and I know that it is dangerous in situations where I should be able to shift the gear and not be moving fast enough to get a dent. I hope Hyundai really looks at this issue and helps us out. Thank you.

The contact owns a 2015 Hyundai Sonata. The contact stated that while driving at approximately 60 mph, the vehicle decelerated independently while the check engine light illuminated. The vehicle was taken to an independent mechanic where it was diagnosed that the sparks plug and the pcv valve needed to be replaced. The vehicle was repaired however, the vehicle check engine light recurred. The vehicle was taken to the dealer where it was diagnose but the failure was undetermined. The vehicle was taken to another dealer st. Charles Hyundai where it was diagnosed but the check engine light continuously. In addition, the contact mentioned while driving, there was a pop noise and noticed white smoke was coming from underneath the vehicle. The contact pulled over to the side and exit the vehicle. The fire department extinguished the fire. A police report was filed. The vehicle was towed to tow lot and was destroyed. The dealer was no contacted. The manufacturer was not notified of the failure. The approximate failure mileage was 143,000.

I have been receiving a �safety stop. Check hybrid system� warning multiple times. I have taken it to Hyundai multiple times telling them of the issue. They kept telling me no issue could be found. The last instance they updated the software in the car in what appears to be a hail mary to say they did something. Last night I was traveling I was traveling on the highway at about 60 mph. The car started dinging and gave me the warning error attached. The car completely lost power and only allowed me to coast. I was lucky enough to barely able to get myself into a location of relative safety. I parked the car and restarted it and was able to drive once again. This continues to be an issue, extremely unsafe, and Hyundai cannot give me an explanation or fix the problem. This is unacceptable and almost lead to a massive accident.

Hyundai reprogramed their theta engines to prevent an ongoing problem related to theta engines not receiving oil to the crankshaft and connecting rod bearings. The software modification was done by an unknown software house. When I got the first notice, I asked both the local dealer, and the official Hyundai site if this software would cut power, potentially at the wrong time, like going up an entrance ramp. I got no response and I found out why. I tried entering a highway where traffic was at 75 mph. When I got onto the ramp the car was running fine. Suddenly the power just went away. I had the gas pedal all the way to the floor and watched the tachometer and speedometer go down rather than up. I pulled off at the next exit and switched the programming on my transmission to normal from econ mode. Up the ramp I went, and car started slowing down. Tried one more time using the sport mode and the power went away. I'm afraid to try and run on a freeway at rush our because of the lack of power. I think the needs to be a review of the software and see if changes can be made.

I'm really at wit's end with what is going on with my car. My car is currently at 104k, its a 2015 Hyundai Sonata sport. A beautiful car with an abundance of serious issues. I've had trouble with my car accelerating for over a month and I've taken it to at least 5 mechanics who have troubled shooted with no success to fixing the issue. The problem: my car hesitates significantly when accelerating and sometimes when it's can't shift gears and I'm easing my foot on and off the gas pedal, it begins to shake while attempting to accelerate. I try not to put the car in sport mode but sometimes this mode is what helps the car shift gears but I don't think this good for the car. So far I've tried changing all of my spark plugs and coils replaced, fuel injectors cleaned (dealership), transmission fluid changed and ecm updated (dealership). Also, the Hyundai dealership diagnosed the issues as an engine problem (intake exhaust and timing chain + tensioner) --- cost of all these things almost $4000!! I just don't understand why the check engine light is not coming on -- which is hinting at the local mechanics that it might be a transmission based issue. No the check engine light has not come on but the car drives really poorly. I'm taking it to a transmission shop and hopefully going to get some answers as to what is going on. This issue is absolutely frustrating and now I'm just looking for real direction by waiting to see if the engine light will come one and throw a code.

Told the Hyundai dealer 2 years(March 2021) ago that I was concerned about my oil light flashing periodically between scheduled oil changes. No action other than oil changes and one time they added a couple of quarts "no charge" as it again was low. Continued to change oil more often than necessary and the frequency increased. Multiple other car repairs have been happening and the oil now has to be added weekly to maintain proper amounts. Had to change spark plugs 2 times with in 5 months and now another engine light came on today 11/15, and when I check the code at a parts store I was told is was a p03001 and p03002 which was something to do again with the cylinders misfiring. Everyone I have spoke to says this is an engine issue and it is under recall. I did place a claim with Hyundai care USA after being told by the dealer that it would be better if I did this instead of them. The assistant manager also confirmed that the engine is covered 100%. I did this in September after the second repairs. The regional manager finally called me back and indicated he agreed about the problem needing to be resolved and would call me after he spoke to the dealer in a day or two. It has been over a week and no one has called. I keep leaving messages. I now have the same error codes, it is November 15 and the spark plugs were all changed less than 2 months ago for the exact same reason. I have been stranded and at times when I accelerate onto traffic the car will not respond. I do not use the interstate anymore as I cannot predict when the car will slow down and not get enough speed and cause an accident. I only drive to work and back right now. I was given this website by the employee at the parts store along with some information concerning p1326 codes and they are engine related. I will upload the most recent repair receipt.

Sonata started having problems with less than 50,000 total miles. The accelerator is flawed and the vehicle cannot keep speed when traveling uphill or get to speed efficiently. The vehicle jerks for a few seconds when pressing the gas and the engine revs but the vehicle does not accelerate like it should. This has almost caused me to have accidents multiple times when pulling out into traffic. The check engine light came on when this started occurring and has been on ever since. I'm having the Hyundai dealership take a look at the vehicle and see if there is anything that can be done.

Vehicle started slowly cranking for a week or so and then while driving in a 55mph zone, speed suddenly dropped to 20 mph with choking to the point of pulling to a safe area and having car towed 11-4-2020.

I was driving to work as I normally would from the university I attend. About half way to my destination the check engine light illuminated and right when I was about to find a safe place to stop the car abruptly stopped in the middle of the highway and stalled on one of the most dangerous highways in the u. S. Being us I-20. I almost immediately got hit from behind however a few vehicles behind me did get involved into an accident due to the my car stopping abruptly with little warning. I called Hyundai immediately and asked for a tow driver however the wait time was excessive and I had to go to work. I was able to start the car after 20 minutes, but it was in limp mode and I pulled off to the side of the road and had to uber to work. The next day I had got a tow truck to pick up my car and take it to the dealership where they said the car had accidentally triggered the knock sensor by mistake and replaced it free of charge. However the very next day it happened again after driving about 30 miles. And I took it back to the dealer they offered the same thing a replacement sensor. When I did some research and the car actually needed a new engine after a recall had been placed. Hyundai refused to replace the engine after the knock sensor deployed. This is Hyundai's issue and it needs to be addressed. I was forced to put the car on the side of my house for the time being and get a rental until I could afford another vehicle. This is very disappointing from a consumers point of view. I filed with the extended warranty campaign txxc and got denied due to the amount of miles on the vehicle. However there was no warning before the engine failed. The car was very well maintained and had regular oil changes with full synthetic oil every 5k miles. No precursors to the engine failing occurred, like a knocking or jerking or anything. This is an issue that Hyundai need to address. I am very disappointed. Campaign reference number for my case 17507525.

While driving on a busy four lane I entered a turn lane to cross traffic. Immediately after I engaged the accelerator the vehicle lost all power and steering, with a alarm stating �hybrid system warning-do not drive�. One vehicle narrowly missed hitting my car, (as it completely lost all power and steering and left me stuck in the middle of on coming traffic). Researching today I see this is common between 2012-2016 especially. This is a very dangerous situation that was narrowly avoided.

While driving down highway car began to smoke from tailpipe and began to lose acceleration while driving on highway. Vehicles check engine light illuminated. Took vehicle to nearest auto part retail store for diagnostic testing. Error code p0014 came up along with 2 other codes. Took vehicle to auto repair shop. Advised the exhaust solonoid had to be replaced along with spark plugs and gaskets due to burning from theta 2. 0l turbo oil feed line. Car not drivable back to houston where I reside. We had to find additional time to stay at hotel and well as pay for transportation back home. My car is still in san antonio. Recall was repaired less than 6 months ago and car now has the same issue.

Driving home and all of a sudden this alert goes off. Brake system warning, pull over now. Check brakes. Car slolws shuts off and I'm stuck on the road. Had to get a tow and now car won't start. Shows same warning when I try to start it.

I was driving to work Friday 12-6 at approx. 7:24am and the check engine light comes on and flashing. I then pulled over to see what was wrong and I turned the car off and back on the car will then only accelerate to 10 mph then slowly accelerate but will not go past 63. I was able to drive it back to a mechanic who then diagnosed it and stated it was a p3126 obd-ii diagnostic powertrain (p) trouble code description p3126 engine trouble code is about exhaust gas recirculation sensor b circuit high. Reason for p3126 code the reason of p3126 obd-ii engine trouble code is engine oil temperature sensor malfunction. P3126 code on vehicles with electronically controlled automatic transmissions, the 3-4 shift solenoid is responsible for actuating the hydraulic circuits to activate clutches or bands that change gears inside the automatic transmission. Contacted Hyundai and justin asked me was the check engine flashing I advised him yes. He said it was more than likely a recall. He made me an appt for Tuesday 12-10 @ 7:15am. I proceeded to drive my vehicle to Hyundai and I was told it's not a recall and they are going to charge me $175 just to diagnose the problem. I drove it back to my job in flowery branch GA and contacted geico to tow it back to my house.

Tl the contact owns a 2015 Hyundai Sonata. While driving various speeds, the brake pedal was applied, but the vehicle failed to respond and continued to move and idle. There were no warning indicators illuminated. The vehicle was towed to an independent mechanic who stated that the brake sensors and throttle body needed to be replaced. The vehicle was repaired. The local dealer was not contacted. The manufacturer was contacted and provided case number: 16052684. The contact requested reimbursement, but was denied. The failure mileage was 35,137.

Scc refuses to come on saying scc conditions not met. When it does come on it turns off by itself saying scc conditions not met or check scc radar. Sometimes does not detect vehicle in front of me. Goes in and out between detecting vehicle in front of me and not detecting it. Randomly says check scc radar. Does not stay engage, turns off by itself, will not turn back on. The car was in motion on a highway.

Around 25000 miles, after start, strong engine vibration with no power - about to stall. Dealer changed variable charge motor after 5 occurrence of similar situation. After few months at 29000 miles, 2015 Sonata se (2. 4l 4 cylinder engine) lost power and stalled in the middle of city street, while driving. Could have caused big accident if I was on highway. Car was unable to restart. Towed to dealer and replaced accelerator position sensor. Could be related to issue with 2011-2014 Sonata engine recall since my 2015 Sonata uses almost same theta-ii engine.

My 2015 Hyundai Sonata was purchased brand new, and have had multiple power/acceleration issues; however, the most recent happened on March 19, 2019. While driving on a street (evening time) with the speed limit of 45, my car started to sputter/jerk back and forth, abruptly bringing my car to a speed limit of under 15 mphs. I tried to accelerate, but the gas paddle was unresponsive. This a major hazard and extremely dangerous. This is a known issue, and Hyundai corporate office is aware (I called after the first incident), and is not doing anything to rectify the issue. Nhtsa need to make the manufacturer accountable, by reason of the numerous complaints about the same issue. I was close to being rear-ended, and if nothing is rectified, it will cause an owner to be severely injured.

Engine hesitates to put out power when taking off from a stand still. Transmission upshifts instead of downshifting when pressing pedal pedal 50% of the way. These problems occur in city driving.

The contact owns a 2015 Hyundai Sonata. The contact stated that while driving at various speeds, the power steering assist would intermittently fail as the reduction in power steering assist would illuminate on the instrument panel. The contact also stated that his vehicle would shut off while driving at various speeds without warning. The contact also stated that the vehicle would independently accelerate as the check engine and oil warning lights illuminated on the instrument panel. The contact had to depress the brake pedal to stop the acceleration. The dealer had yet to be notified of the failure. The manufacturer had been notified of the failure but offered no assistance. The vehicle had yet to be repaired. The failure mileage was approximately 56,000.