Power Train Problems of Hyundai Sonata - part 1

I bought a 2018 Hyundai Sonata a few years back. No warranty. Used. 110,000 miles. A few short months after I purchased it, it stopped working. I took it back to the same dealership where I purchased it and they said they had to replace the coil packs and spark plugs and clean something in the engine out because there's a defect in the engine. I paid $500. Fast forward a few months later. Same thing happens. I take it to an auto repair shop because it's cheaper and the mechanic says he deals with these same issues with other customers who have similar year, make, and models. This pattern continues to this very day. It broke down while I was working my 2nd job. I have a daughter. She plays sports. I have a second job. I need this problem completely alleviated as quickly as possible. Like a lot of the american public, I don't have extra money to keep up with anything beyond the normal maintenance of my vehicle. I keep it up to date with all oil changes. What can you do to get me a vehicle I can trust and it not break down every couple months and cost $300-$600 each time? I don't have good credit (I'm working on that) I have medical issues that I have to visit my doctor for every 3 months. I have the loan through capital one and they don't offer refinancing. My father who has passed was a car salesman his entire career. I just need reliable transportation and if it's a motor problem like they say then I shouldn't be liable to fix it. The manufacturer should. Please let me know if you need any service records from me. Oh and I also have to put about $20 worth of oil in it every week or so between oil changes. My local oil change guys unfortunately know me very well.

See all problems of the 2018 Hyundai Sonata 🔎.

This complaint is not related to the existing recall associated with this vehicle. The vehicle is experiencing a serious loss of power and acceleration issue. The car is unable to accelerate past approximately 60 mph. When pressing the accelerator fully, the vehicle does not respond or increase speed. While attempting to accelerate, the engine rpm increases and then suddenly drops repeatedly, causing the vehicle to struggle to maintain speed. This behavior is consistent and occurs during normal driving conditions. This creates a dangerous situation, especially when merging onto highways or attempting to accelerate in traffic, as the vehicle cannot respond when needed. The issue has occurred multiple times and makes the vehicle unsafe and unreliable to operate.

See all problems of the 2016 Hyundai Sonata 🔎.

The bearing failure from the metal debris had been progressing silently for a long time. You can’t feel or hear it happening gradually. Then at some point the damage crosses a threshold where: ?the oil can no longer circulate properly ?the crankshaft bearings completely fail ?internal metal parts make contact with each other ?everything locks up instantly.

See all problems of the 2015 Hyundai Sonata 🔎.

Sudden loss of acceleration. This occurred while making a left turn across traffic from a stop. At approximately 7mph the car would not accelerate any further. I was luckily able to coast the vehicle into a center turn lane. Upon coming to a stop I was unable to get any acceleration. The vehicle was turned off and turned back on again and operated normally. There were no trouble codes displayed.

See all problems of the 2024 Hyundai Sonata 🔎.

Car was parked, full stop, doors shut, seatbelt on. Foot on brake. Car then seemed to lurch forward by itself forward hitting parking cement block. Put in reverse to back away and car stayed still. . . Then I tapped the gas again to back up and insted vehicle plowed forward. Instead. Of reverse . . . Went over the parking block and hit concrete beam in front, when the car should have backed up in reverse. I'm a person who drives speeed limits, and ulta careful when I drive, and parked at this place/spot for years. This has never happened not sure why it did. No injuries or other people involved thank god, but scared the heck out of me. Wracking my brain, my recalls and software and service appts are up ro date. Nothing out of ordinary that day. I'm confused and shaken, why the first lurch forward and why did going in reverse move it forward? ugh. It drove home fine. Commute to work daily for years, no issues. All I can guess is gear didn't click to reverse and was somehow in drive? ive been going over the possibilities in my head for human error but they dont make sense - again I've been driving for 40 years. If it happens to other models, would love to know! car will go to repair tomorrow as "my fault" via insurance, hoping they can see more if any error codes, to at least say if reverse didn't engage or something else happened. May have been human error but it's so out of the ordinary for me. Thanks!.

See all problems of the 2023 Hyundai Sonata 🔎.

Vehicle suddenly lost heat in 30 degree weather. No warnings, check engine light, or temperature gauge indicators came on. Lucky made it to a parts store and found out I was extremely low on coolant. Bought coolant and put it in. Made it back to the house and was immediately low again. No visible leaking. Oil was completely fine (1 gallon of coolant would have have left some kind indicator). Realized it was more than likely the ehrs. If this happened during the summer, my engine could have blown due to a poor design causing a major accident.

See all problems of the 2021 Hyundai Sonata 🔎.

Component/system failed: engine – connecting rod bearing failure consistent with Hyundai theta ii engine defect subject to federal recalls and consent orders. The vehicle previously received recall campaign 953 (ksds software update), intended to detect premature rod bearing wear. The engine is currently knocking and has been diagnosed as requiring replacement. The vehicle and engine are available for inspection upon request. Safety risk: rod bearing failure can cause sudden engine seizure or stall while driving, creating a significant crash risk due to loss of power steering and braking assist. Engine failure did occurr despite prior recall software update, indicating potential recall remedy ineffectiveness. Sudden stalling in traffic placed myself and others at risk of collision. Dealer confirmation: Hyundai of north charleston confirmed through warranty history a prior engine replacement request (PA) was submitted by a previous owner but denied. The recall repair was never performed. Current diagnostic findings indicate engine failure consistent with known recall defect. However, Hyundai has refused to perform further inspection or goodwill repair solely due to the vehicle’s salvage branding. Inspection history: the vehicle has been inspected by a Hyundai dealership. No engine replacement was completed. Hyundai customer care has updated case notes but is declining remedy based on title status rather than mechanical condition. Warning lamps/symptoms: the vehicle previously received ksds software update. Engine knocking developed consistent with rod bearing wear. The software did not provide effective prevention of engine failure. The engine now requires replacement. Hyundai is refusing recall-related remedy due to salvage title (predates my wonder ship by many years), despite federal recall obligations applying to the vehicle VIN. This complaint concerns potential failure of recall remedy effectiveness and denial of defect-related inspection.

Passenger seat belt doesn’t click in. Miss fire poor acceleration exhaust leak power lost mechanic can’t find the problem check engine light on.

See all problems of the 2009 Hyundai Sonata 🔎.

P0471 code before 55k miles even after repair is made.

The vehicle developed a progressive engine failure beginning in early 2024, including loud knocking noises at cold start and visible white/gray/black exhaust smoke. The condition worsened over time. In February 2026, the failure escalated to active oil discharge from the exhaust pipe while the engine was running. Oil exiting through the exhaust indicates internal engine failure (such as piston rings, cylinder walls, or valve seal failure), not an external leak. This creates a safety risk including potential loss of power while driving, risk of engine seizure, and possible fire hazard due to oil in the exhaust system. The condition has been documented on video multiple times and was shown to dealership personnel. The vehicle was taken to a Hyundai dealership for evaluation and remains available for inspection. Despite this, no written diagnostic findings or repair determination have been provided. The issue has been persistent, progressive, and reproducible, and represents a potential defect affecting engine integrity and safe operation of the vehicle.

Unknown what system failed. The vehicle is at an impound lot and can be inspected on request. Police and fire department were on the scene. Police did provide a report # , and fire department provided a fire rescue case number. Safety of driver was put at risk due to the fire and potential for burning or even death. Other drivers could have been at risk if traffic had not allowed for quick movement to side of the road. No warning lamps had been on prior to the drive and none prior to fire. First indication was a burning smell while driving. As pulling over, another driver honked to alert to fire he could see from rear of CA,. Before I noticed the flames. Upon getting out of car first flames I saw appeared to be coming from under passenger side of car. The fire department arrived about 15 minutes after pulling to side of the road. The car was fully engulfed in flames. They then extinguished the fire. Police saw vehicle and insurance will examine. Apparently this is a known issue in Hyundai of which this vehicle had no open recalls pertaining to such.

My 2016 Hyundai Sonata (2. 0t/2. 4l engine) has been experiencing loss of motive power and severe engine stumbling at stoplights, creating an unreasonable risk of a crash in traffic. The check engine light is on with dtc p0010. Upon inspection, the internal oil seal plug at the intake camshaft e-cvvt has become unseated, causing an active oil leak. This matches the exact defect and symptoms (elevated idle of 1,200–1,400 rpm and power reduction) described in Hyundai service campaign tx3 (TSB 15-01-022-1). While that campaign only applied to 2015 models, my 2016 vehicle has suffered the identical failure. I am requesting that this safety-related defect be investigated for 2016 models to prevent potential engine fires from oil leaks or accidents from sudden power loss.

My engine light come on. Air flow notification come on. I had a brake cleaner notification come on.

See all problems of the 2025 Hyundai Sonata 🔎.

At least 8 times when driving the car the transmission switches from the drive “d” position to the park “p” position and I have to cut off the car and then restart. It is very dangerous as I can be rear ended which can result in personal injury as well as an insurance claim. I’ll put the last date it occurred but started experiencing soon after I bought car.

My vehicle has a documented excessive oil?consumption defect. After a 1,000?mile oil?consumption test performed by a Hyundai dealership, the engine was found to have consumed 2. 8 quarts of oil, which is far above normal and poses a safety risk. The dealer referenced TSB 23?em?008h and recommended a chamber cleaning but could not guarantee it would resolve the issue. Hyundai motor America declined to cover the repair and refused to escalate my case. This level of oil consumption is consistent with known theta ii engine defects that have led to engine seizure, stalling, and fire in other vehicles. I am reporting this as a safety concern due to the risk of sudden engine failure while driving.

See all problems of the 2017 Hyundai Sonata 🔎.

On January 6, 2026, during my morning commute in heavy traffic, my 2023 Hyundai Sonata engine unexpectedly turned off, causing a sudden loss of power. This created an extremely dangerous situation, and I came very close to being involved in a major collision. While I was fortunate to avoid a crash, the incident posed a direct threat to my safety and life because of the dense surrounding traffic.

My 2022 Hyundai Sonata hybrid started blowing white smoke from the exhaust. Took it to the dealership and was advised the valve that controls antifreeze failed and leaking antifreeze in exhaust. This caused the engine to overheat and would cause the engine to blow up. My car has 83,000 and was told the manufacturer warranty only covered to 80,000 and extended warranty would not cover the part. Was told it would cost 2659 to fix. This is part of the hybrid power train and should be covered under the 100,000 Hyundai warranty. I have seen the same issue with other Sonata hybrids on the internet that is doing the same as mine. Hyundai needs to recall for this since it is a needed component for the engine.

See all problems of the 2022 Hyundai Sonata 🔎.

While driving with my family on a busy freeway at approximately 70 mph, our vehicle suddenly displayed a loud, urgent warning: “hybrid system warning – safely stop and do not drive!” at the same moment, the car lost the ability to accelerate without any prior signs of trouble. We were extremely fortunate to have enough momentum to coast to the shoulder and shut the vehicle off, unsure of how serious the issue might be. Being stranded without warning on a high?speed highway put my entire family in a dangerous situation. After a few minutes, we restarted the car to see if we could at least get it off the freeway. The warning had disappeared, and the vehicle drove normally, allowing us to take back roads home. The lack of any prior symptoms makes this even more concerning. Losing acceleration at highway speeds with no warning is a major safety hazard. We took the vehicle to a dealership immediately, but because the warning light was no longer active, they were unable to diagnose the problem. A few days later, the same warning appeared again—this time only a couple minutes from home. I turned around immediately for safety, parked the car, and once again the warning disappeared as soon as the vehicle was shut off. At this point, we have a car sitting in our driveway that we do not feel safe driving. The dealership cannot identify or repair the issue unless the warning is active, & even then, they cannot guarantee that a diagnostic code will appear. After researching this problem online, it’s clear that many other Hyundai owners are experiencing the same issue, often spending thousands of dollars without a definitive fix. Despite how common & dangerous this problem appears to be, there are no recalls & no consistent guidance from dealerships. This situation is unacceptable from a safety standpoint. A vehicle that can suddenly lose power at highway speeds—with no warning and no reliable way to diagnose the cause—poses a serious risk to everyone and needs to be investigated.

See all problems of the 2014 Hyundai Sonata 🔎.

I own a 2021 Hyundai Sonata 1. 6t, which has an open NHTSA safety recall (25v796000) related to fuel tank pressurization and fire risk. I brought the vehicle to an authorized Hyundai dealership due to a check engine light, reduced performance, and dtc p14ee, which aligns with the recall condition. The dealership refused to treat the concern as recall-related unless I paid a diagnostic fee and later attempted to reclassify the issue as a customer-pay fuel pump repair. During this visit, the dealership replaced a fuel system sensor without my authorization, which I did not approve or consent to. The dealership has not provided documented test results explaining how the recall condition was ruled out and has not documented recall inspection on the repair order. I expressed that I do not feel safe driving the vehicle due to the fuel system recall and drivability issues. The dealership also refused to provide alternate transportation. I am concerned the recall is not being handled in compliance with NHTSA requirements and that unauthorized repairs were performed while attempting to shift a recall-related condition to the customer. I am requesting review of recall handling and dealer compliance.

Oil pressure sensor failure caused oil to leak into the injector harness damaging components and engine shutdown. Because this was a sudden engine shutdown and safety-related loss of motive power caused by an oil pressure sensor failure this presents a safety risk.

Vehicle without warning will start to jerk then go into “limp” mode. Pressing on gas pedal makes the revving noise but with not physical movement made. This has happened on multiple occasions (13 times in 4 months) including in the snow and on the interstate while driving at 70mph where no shoulder is available to pull over. Car was taken to dealership 3 different times with no actual diagnosis, tests were ran all 3 times with nothing. Eventually the 3rd time at the dealership I was told the transmission was being replaced although they were not sure what actually caused the issue (this is written in the service report by the rep/mechanic). Car remains unsafe and unreliable. Livelihood of myself, family and other drivers is at risk everytime I put the car in drive due to this mechanical issue. No warnings no power no fix.

Subject: excessive engine oil consumption – 2016 Hyundai Sonata I am reporting an ongoing and excessive engine oil consumption issue with my 2016 Hyundai Sonata that I believe may represent a safety defect or other significant reliability concern. The engine is burning oil at a rate far beyond normal expectations (requiring frequent top-off well below recommended mileage intervals), resulting in dangerously low oil levels while driving. I have maintained the vehicle per manufacturer recommendations and documented oil add-ins and dealer visits, but the problem has worsened over time. Despite presenting this problem to my Hyundai dealership, they have declined to authorize engine cleaning or further corrective action due to the mileage. I am struggling with high oil consumption and potential risk of engine failure while driving. This issue is not unique to my vehicle — numerous similar complaints exist in Hyundai forums and in other owners’ submitted complaints (e. G. , reports of more than 1 quart consumed every ~500–1,000 miles and sequences of denied repairs) which suggests a broader pattern of oil consumption failures for this model year. Auto safety +1 I believe this may represent a safety defect because loss of engine oil can lead to engine seizure or failure without warning, increasing the risk of a crash or injury. Please review this complaint, add it to the NHTSA vehicle database, and contact me if further information is needed.

While driving on the highway, my 2018 Hyundai Sonata experienced sudden loss of engine power and became undrivable. The failure occurred without warning at approximately 86,500 miles. At the time of the incident, there were two children in the vehicle, and the breakdown occurred at night in cold temperatures (approximately 20°f). An authorized Hyundai dealership later diagnosed zero compression in cylinder 3 and confirmed a cracked piston, recommending full engine replacement. The sudden loss of power while driving created a safety risk due to traffic conditions and environmental exposure.

Airbags did not deploy no indicator light came on before nor after I was struck from my driver side front area and yes it is available for inspection upon request. My safety along with my sisters safety was put at risk due to the negligence and cheapness of the dealership I purchased the car from also from there misleading information and improper inspection before selling me the car car has not been reproduced or confirmed the car was inspected by a third party appraisal company for damages amounts there were no lights on at all before the accident and I am pretty certain that the dealership cleaared the codes before selling me the car.

The contact owns a 2016 Hyundai Sonata. The contact stated that while driving and depressing the accelerator pedal, the vehicle failed to respond or exceed 30 mph. The contact stated that the speedometer reading was lagging. The contact stated that the vehicle accelerated as intended while depressing the accelerator pedal with more force. The vehicle was taken to an independent mechanic, where the camshaft position sensor was replaced. Additionally, the contact stated that the starter was previously replaced due to the engine's failure to turn over while starting the vehicle. The contact stated that upon switching to sport mode and driving 40 mph, the vehicle jerked and lost motive power. The contact shifted to neutral(n) and was able to pull to the side of the road. The vehicle was able to restart the vehicle, but the vehicle was undrivable. The vehicle was towed to an independent mechanic, where it was determined that the failure could be an electrical failure or that an engine replacement was needed. The vehicle was not repaired. An unknown dealer was notified of the failure, but the vehicle was not diagnosed or repaired due to the cost. The manufacturer was not notified of the failure. The failure mileage was approximately 152,000.

On November 10, 2025, my 2016 Hyundai Sonata hybrid (VIN [xxx] , approximately 150,000 miles) experienced a sudden loss of power while I was turning right and accelerating into traffic. The vehicle immediately entered limp mode with flashing warning lights and audible alerts. The vehicle lost normal propulsion and could not accelerate properly, creating a dangerous situation as it was blocking a traffic lane. I was forced to limp the vehicle into a nearby parking lot to get out of traffic. The vehicle was not safely drivable afterward and was towed home. A few days later, the vehicle was towed to murdoch Hyundai in lindon, utah, for diagnosis. The vehicle was found to have diagnostic trouble code p1326, which Hyundai identifies as activation of the knock sensor detection system (ksds) related to connecting-rod bearing wear. This condition is part of Hyundai’s known engine defect and safety recall/warranty extension programs. During inspection, the dealer observed that the valvetrain did not show signs of neglect or sludge, which is inconsistent with oil starvation or severe maintenance neglect. This further supports that the failure is consistent with the known connecting-rod bearing defect addressed by Hyundai’s ksds safety recall, rather than a maintenance-related issue. This is a safety issue because sudden loss of propulsion or reduced power while entering traffic creates a high risk of collision. Hyundai customer care has been unwilling to open a new case number or escalate review, and the dealer has indicated possible denial of engine replacement coverage based on incomplete oil-change records, despite the vehicle exhibiting the ksds safety condition. I am requesting NHTSA review of this safety-related defect and the manufacturer’s handling of ksds/p1326 failures. Information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

The vehicle experienced an engine and power train failure while driving on the highway, resulting in sudden loss of power. The electrical system also failed after the dealer visit, causing the battery to die every morning. Yes, the vehicle is available for inspection upon request. My car suddenly lost power on the highway and would not accelerate, forcing me to pull over on the shoulder with traffic moving around me. This created a serious risk of a rear-end collision or crash. Additionally, after the dealer visit, the electrical system began failing and the vehicle has been completely dead every morning, leaving me stranded with a child and unable to reliably start the car. The problem has not been reproduced because the check engine code cleared itself after the incident; however, the symptoms absolutely remain. The dealer refused to diagnose the loss-of-power event because the code was cleared, and they returned the vehicle to me with a dead battery. The electrical issue (car dying every morning) has been happening consistently since the dealer visit. The vehicle was taken to a Hyundai dealership immediately after the incident, but they refused to diagnose the loss of power due to the code being cleared. A mobile mechanic scanned the code at my home before the tow, but the code disappeared afterward. The electrical failure began after the dealer visit and has not been properly inspected by Hyundai. Yes. While driving on the highway, the check engine light came on and the car immediately lost power and would not accelerate. After the dealer visit, the car has been completely dead every morning and requires a jump to start. These symptoms began on the same day as the highway incident and continued after Hyundai serviced the vehicle.

The engine/powertrain on my 2015 Hyundai Sonata (VIN: [xxx] ) has failed due to extremely low compression in all four cylinders, causing severe misfires, hard starting, loss of power, and intermittent rattling noises, and the vehicle is currently available for inspection at the Hyundai dealership. This failure created a safety risk because the engine hesitates, struggles to start, and can stall or lose power during driving, which could lead to a loss of control or an inability to accelerate in traffic. The problem has been confirmed by both an independent mechanic and the Hyundai dealership, who documented low compression across all cylinders. The vehicle has been fully inspected by the dealership on Hyundai’s behalf after I opened a case with the manufacturer. Prior to the complete failure, the car showed warning symptoms such as repeated cylinder 4 misfires, rough starting, reduced power, rattling noises on startup, and the check engine light appearing several times beginning earlier this year. Information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

During multiple dealership visits in 2025, my 2018 Hyundai Sonata limited 2. 0t was repeatedly returned in unsafe condition. Southern Hyundai installed both front cv axles and torqued them incorrectly. The right axle was later confirmed under-torqued by about 50 ft-lbs, and the left axle was later found over-torqued 40ft-lbs priority Hyundai later identified and corrected the under-torqued right axle, which briefly improved symptoms but did not resolve the underlying issue. When I returned for a follow-up on October 29, 2025, for a documentation-only appointment due to an active corporate case, the dealer ignored my instructions and altered evidence by loosening and re-torquing the left axle nut without consent. They recorded the torque at 250 ft-lbs in the repair order but failed to capture the required photos or before/after readings and referenced the wrong vehicle’s torque specification (Hyundai elantra) in the documentation. Since then, the vehicle has continued to show steering pull, vibration, and instability at speed. Several visits showed only 0–3 miles of verification driving after safety-critical repairs involving brakes, suspension, and driveline components. Aftermarket parts were installed when oem parts were promised, and uneven tire wear developed quickly. Safety risks include wheel-bearing damage, steering loss, and driveline separation due to repeated improper torque and altered evidence. Independent firestone and Honda technicians have verified these issues. The matter remains under active Hyundai corporate case #[xxx]. Information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

The contact owns a 2021 Hyundai Sonata. The contact stated that while driving at 30 mph and depressing the accelerator pedal, the vehicle failed to respond and lost power. The vehicle was coasted over to the right side of the road, turned off, restarted, and returned to normal functionality. An independent mechanic was contacted. The vehicle was taken to an independent mechanic to be diagnosed; however, the diagnosis was unknown. The vehicle was not repaired. The contact related the failure to NHTSA campaign number: 22v746000 (power train); however, the VIN was not included in the recall. The manufacturer was not notified of the failure. The failure mileage was 35,000.

High engine oil consumption 2 qts every 1k miles.

Good day, please note that most of my communication with Hyundai has been over the phone. I sent one an email shortly after the event, and after following up on the phone, I received this following string separately. I can forward you more along the way, but Hyundai is in possession of the call recordings. I was hoping they would cover my repairs, my engine had a lifetime warranty, but during this process I learned that there was a recall for this car that I was never aware of as the new owner. I needed a software update to get any repairs covered. Please reach out to me for more info!.

See all problems of the 2011 Hyundai Sonata 🔎.

Vehicle stalled while driving.

See attached document for complaint.

The contact owns a 2024 Hyundai Sonata. The contact stated that while attempting to accelerate to overtake another vehicle at approximately 60 mph, the vehicle unintendedly decelerated to approximately 20 mph instead. The contact pulled over to the side of the road, turned off the vehicle for approximately 20 minutes, before restarting and continuing to drive. There were no warning lights illuminated. The failure had occurred three times. The vehicle was taken to a certified mechanic, who diagnosed that the transfer case had failed and referred the contact to the dealer for assistance. The vehicle was taken to the dealer, who was unable to determine the cause of failure. The vehicle was repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 16,500.