Engine And Engine Cooling Problems of Hyundai Sonata - part 1

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.

See all problems of the 2018 Hyundai Sonata 🔎.

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.

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Once the car gets slowed down and reaches 20 mph of speed by applying the brake or not. It gives a sudden jerk, which causes immediate reduction in speed.

See all problems of the 2009 Hyundai Sonata 🔎.

While driving my 2015 Hyundai Sonata, the vehicle suddenly lost power and entered limp mode. A loud engine knocking noise was present, and acceleration was severely limited, creating a safety risk in traffic. The check engine light illuminated at the time of the failure. An independent mechanic confirmed diagnostic trouble code p1326, related to the engine knock sensor detection system designed to detect early engine bearing failure. The condition occurred without warning. The vehicle is currently not being driven to prevent further damage and is available for inspection upon request. Sudden loss of power while driving poses a serious safety hazard. This appears to be a known engine defect affecting similar vehicles.

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Please see the attached paperwork and I have more if needed. I am not receiving any help from the local Hyundai dealership in which I purchased the car, and I have reached out to the main headquarter. This is the 2nd Hyundai I purchased, and I was not made aware of the oil consumption issue.

See all problems of the 2017 Hyundai Sonata 🔎.

I had recall 162 - engine replacement completed in 2024 , now I have fuel leak at high pressure fuel pump, the pump that is a component of the engine has now failed which was installed during the engine replacement which can cause a major fire.

See all problems of the 2014 Hyundai Sonata 🔎.

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.

The contact owns a 2011 Hyundai Sonata. The contact stated that while driving approximately 30 mph, the vehicle unexpectedly lost motive power. There was no warning light illuminated. The vehicle became inoperable and could not be restarted, and the vehicle was towed. The vehicle was towed to a dealer, where it was diagnosed with engine failure. The dealer stated that the failure was related to a previous recall associated with the VIN; however, the recall number was not provided. The dealer informed the contact that the engine needed to be replaced. The vehicle was not repaired. The contact was referred to the manufacturer for assistance. The manufacturer was notified of the failure but denied coverage for the repair and alleged that the engine failure was a result of negligence in the maintenance records. The approximate failure mileage was 183,000.

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Engine started rough idling and knocking. Took to a mechanic who found metal particulate in the oil and the engine spun a bearing.

While driving, vehicle slowed down abruptly and stopped. It was flashing “vehicle not safe to drive”. This happened before hen I got a new engine 2 years ago. Even with a new engine now it is happening again. I took it to Nissan moreno valley and paid $240 for diagnostic only to find out there a software update they had to do with a tablet. No work needed to be one just a software update hooked up to their system. Hyundai cooperate would not assist to over this fee. I like have crashed with this happening. The car just stops with no warning and it’s extremely dangerous how it cuts off while driving. Luckily I was on the streets not freeway.

See all problems of the 2013 Hyundai Sonata 🔎.

The 2017 Hyundai Sonata has had an ongoing engine malfunction defect that is causing engine knocking, stalling, and smell and rapid depletion of oil. The continuous issues are concerning especially when the car is not driven on a regular basis as it is utilized as a second vehicle. This has been a noticeable issue for quite sometime now. I have taken the car to the Hyundai dealership on multiple occassions after notably heavy oil consumption in a short time period in between scheduled oil changes. I am told by the dealership that it is evident that the engine is rapidly processing and burning oil inappropriately from a possible manufacturing defect recall related to connecting-rod bearing failure that was issued by Hyundai for various Hyundai models. The damaged engine may stall, increasing the risk of a crash. In addition, oil may leak onto hot exhaust components, increasing the risk of fire.

I was driving my 2021 Hyundai Sonata at approximately 3:00 am when the vehicle suddenly began shaking and vibrating. While stopped at a traffic light, the check engine light illuminated, and the engine was shaking severely. I immediately pulled over and shut off the engine. After waiting approximately one hour, I restarted the vehicle, but it was only able to drive very slowly. The following day, the vehicle was towed to a local repair shop. Diagnostic testing showed a cylinder 3 misfire, along with evap system errors and faulty fuel injector issues. This failure occurred without warning and created a potential safety risk while driving. I am concerned this may be related to a defective fuel system.

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I have taken my vehicle to a certified Hyundai dealership multiple times due to intermittent starting issues. The car will unlock remotely, and the lights and electrical components will turn on, but the engine will not start. When this happens, I press the ignition button to turn the vehicle off and then try again. Sometimes it eventually starts, but there have been several occasions when it would not start at all, forcing me to call for a tow or have the battery jumped. This issue occurs most often in cool or cold weather. I had a brand new battery installed at the dealership in July 2025, yet the problem has continued. I have been dealing with this for over a year and have even been stranded out of state in below-freezing temperatures. Each time I bring the vehicle in, the dealership states they are unable to replicate the issue while it is in their service department.

See all problems of the 2020 Hyundai Sonata 🔎.

I am filing a complaint against Hyundai motor America regarding denial of defect coverage for my 2016 Hyundai Sonata (VIN: [xxx] ). The vehicle is experiencing excessive oil consumption and triggered diagnostic code p1326. The dealer confirmed only one quart of oil remained in the engine and noted a valve cover gasket leak. Hyundai’s tech line instructed a gasket replacement and oil consumption test, but Hyundai corporate formally declined coverage, citing mileage and second-owner status. This is not a routine warranty claim but a defect claim. Oil consumption defects in Hyundai theta engines are well-documented and have been subject to recalls, technical service bulletins, and class actions. Defect coverage should not be limited to first owners. I am requesting reimbursement for the valve cover gasket repair, acknowledgment of the oil consumption defect, and corrective action to ensure Hyundai honors defect-related coverage fairly. Information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

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.

Engine losing power and metal shavings in oil and engining shutting off.

Engine makes rattling and knocking noises. Transmission hesitates and jerks suspension front struts and rear shocks are bad. Possible the isolators. Having horrible back pain when riding in car. Starter intermittently doesn't work lane keep assistance goes over small bump in road will make car drive in opposite lane into on coming traffic. Took car to tameron Hyundai in birmingham on the 29th of December 2025. Told them everything thats going on with the car. They did nothing about any of the issues. Car has 55,000 miles on it as that is when all problems have incurred. 60000 mile warranty expires in February of this year.

My 2017 Hyundai Sonata sport limited 2. 4 has a known engine defect causing excessive oil consumption. The vehicle was at an authorized Hyundai dealership for the oil consumption test and had been approved for a new engine replacement. Prior to the repair, I completed $2,300 in maintenance, specifically an oil combustion cleaning and spark plug replacement, which the dealership said was required to perform the oil consumption test. While the vehicle was in the dealership’s custody, it caught fire on 12/19/2025 at world Hyundai matteson. No one was injured, but the car was destroyed. This occurred while the vehicle was under warranty repair, creating a serious safety risk. I am submitting this complaint to document the fire and the associated safety issue with this engine defect.

Cylinders in the engine are misfiring causing car to shake. Pistons in the engine are having trouble keeping the air compressed so psi to continue to decrease causing the misfire.

Subject: non-collision engine compartment fire - 2010 Hyundai Sonata (VIN: 5npeu4af3ah630796) ?"on Dec 19 2025, my 2010 Hyundai Sonata suffered a sudden, non-collision fire that originated in the engine compartment. While there are currently no 'open' recalls on this VIN, I am formally reporting this incident as it matches the failure patterns documented in NHTSA defect petition dp18-003 regarding non-crash fires in Hyundai/kia vehicles. ?preliminary inspection of the damage shows characteristic signs of a manufacturer defect, specifically potentially related to a connecting rod bearing failure leading to an engine block puncture and oil ignition, or an electrical short in the abs module—both of which have been subjects of major Hyundai fire investigations and class-action settlements (e. G. , engine ii settlement).

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The contact owns a 2011 Hyundai Sonata. The contact stated that while driving approximately 65 - 70 mph, there was a grinding sensation coming from the front wheels, and the grinding sensation was felt in the steering wheel. The vehicle was taken to the dealer, who diagnosed that the rod bearings and hubs had failed, causing the grinding sound. The contact was informed that the rod bearings and hubs needed to be replaced. The vehicle was towed to a certified mechanic, and the vehicle was repaired. The contact stated that while driving at various speeds the following day, there was a loud grinding sound coming from the vehicle. The sound also occurred while the vehicle was parked. While attempting to accelerate from 25 - 35 mph, the engine started knocking, and the vehicle clunked and jerked. The vehicle decelerated, and the contact pulled over to the side of the road. The contact became aware that the accelerator pedal was not operating as needed. While on the side of the road, the contact turned off the vehicle and attempted to restart the vehicle; however, the vehicle failed to restart. The vehicle was towed to a certified mechanic, who diagnosed that the engine had failed, and the mechanic recommended the engine replacement. The vehicle was not repaired. The vehicle was towed to a different dealer, capital Hyundai of greensboro (801 e bessemer Ave, greensboro, nc 27405), and the contact was informed of NHTSA campaign number: 15v568000 (engine). The vehicle was not repaired because the manufacturer stated that the maintenance history was not satisfactory enough to warrant an engine replacement. The failure mileage was approximately 138,000.

The contact owns a 2018 Hyundai Sonata. The contact stated that while driving approximately 60 mph, the vehicle started to vibrate roughly. The contact felt the vibration in the steering wheel. The check engine warning light was illuminated. The contact slowed down and pulled off the roadway. The contact turned off and restarted the vehicle and was able to shift to drive(d); however, the vehicle was hesitating and failed to accelerate as needed. The contact drove the vehicle to an independent mechanic at speeds no greater than 40 mph. The mechanic scanned the vehicle and retrieved codes for a misfire in the engine. The mechanic advised the contact to take the vehicle to a dealer for assistance. The vehicle was towed to the local dealer. The vehicle was not yet diagnosed or repaired. The manufacturer was informed of the failure. The contact requested an engine replacement that was denied by the manufacturer. The failure mileage was approximately 138,000.

Manufacturer has refused engine replacement under federal ksds recall settlement without providing causation proof. Owner has maintenance records. Request NHTSA compliance review.

Manufacturer is refusing recall engine replacement alleging neglect without proof of causation. Vehicle has documented maintenance. Denial appears improper under recall compliance law.

Unknown- while driving on highway, from 70 mph speed the car suddenly lost acceleration and speed dropped. No response to accelerator. Even with pushing the accelerator high, car will go in high rpm and speed will barely reach 40 mph. I was lucky that there was no other vehicle behind me, especially heavy automobile like semi truck as it would have crashed in me from behind due to sudden propulsion loss. The car started working fine next day. I took it to dealer and they couldn't find any error code but said it could be 12v battery bms software update and they updated it. They mentioned that this is not a safety issue which is mind-blowing and concerning as this is a major safety hazard. I would request you to investigate this further and if this is a software issue then please direct Hyundai to update this with all vehicles and cover the cost for those who have had to pay for it.

See all problems of the 2023 Hyundai Sonata 🔎.

My 2014 Hyundai Sonata experienced a p1326 engine fault code, which activates the knock sensor system due to engine bearing wear. This condition is directly related to Hyundai’s safety recall 17v226 (theta ii engine). The Hyundai dealership submitted my case to Hyundai corporate, and Hyundai denied the repair solely because my vehicle has over 150,000 miles. A manufacturer cannot refuse a federal recall repair due to mileage, and Hyundai’s engine recall has no mileage or time limit. The denial places me in an unsafe situation, as the recall defect can cause engine seizure or stalling while driving. I am requesting NHTSA intervention.

The contact owns a 2018 Hyundai Sonata. The contact stated that while driving at an undisclosed speed, the low oil warning light illuminated. The vehicle was taken to the dealer, but was not diagnosed or repaired. The dealer advised the contact to have an oil change performed and then return the vehicle after 1,000 miles of driving. The contact stated that after returning the vehicle to the dealer, the vehicle was not diagnosed or repaired. The manufacturer was made aware of the failure. The approximate failure mileage was 99,000.

My Hyundai is experiencing severe and continuous engine oil consumption that creates a safety risk. The vehicle loses a significant amount of oil within 1,000–1,500 miles, sometimes showing almost no oil on the dipstick despite recent oil changes. There are no external leaks, no burning smell, and no visible oil under the car. The cause remains unknown, but it appears to be internal engine burning or a manufacturing defect. I have taken the vehicle to the Hyundai dealer multiple times. They performed oil consumption tests but either reported “normal results” or did not provide clear explanations. The issue continues exactly the same. I also contacted Hyundai corporate, but no meaningful assistance or goodwill support was provided. The dealer acknowledges no leaks but still refuses to repair or replace the engine. This problem is dangerous because the oil level drops without warning lights or error codes. If I do not manually check the dipstick, the engine could run dry and seize while driving. Sudden engine failure on highways or in traffic can cause accidents. I now have to frequently top up oil just to keep the engine alive. I have maintained the vehicle properly and completed all requested tests. The cause is still unknown, but based on similar Hyundai cases, it may involve piston rings, valve seals, or internal engine wear. Many Hyundai owners report the same issue, suggesting a broader defect. The dealer’s only advice is to “keep monitoring oil,” which is not a safe long-term solution. This defect poses a serious safety concern and financial burden. I am filing this complaint so NHTSA can investigate, as the engine may fail unexpectedly, putting me and others at risk.

The contact owns a 2013 Hyundai Sonata. The contact stated that while driving at an undisclosed speed, the vehicle stalled, with an abnormal knocking sound coming from the engine compartment. The check engine warning light was illuminated. The contact was able to restart the vehicle; however, the failure persisted. The contact previously received notification of NHTSA campaign number: 17v226000 (engine and engine cooling). The vehicle was taken to the dealer, where it was diagnosed, and determined that the engine short block had failed and needed to be replaced. The contact was informed by the dealer that the vehicle would not be serviced under the recall. The contact was offered a buyback option for the vehicle and was also offered a loaner vehicle. The vehicle was not yet repaired. The manufacturer was made aware of the failure. The failure mileage was not available.

Vehicle: 2013 Hyundai Sonata VIN: [xxx] mileage: [163,000] summary: theta ii 2. 4l gdi engine bearing failure (recall 953 / 20v-393) – severe knocking, risk of sudden engine seizure/fire. Dealer refuses lifetime-warranty repair and forced consumer to pay towing to avoid lien/fees. Description: this vehicle is covered by NHTSA recall 20v-393 (campaign 953) and the court-approved theta ii engine class-action settlement providing a lifetime warranty for rod-bearing failure. The engine now has loud knocking from failed rod bearings – the exact defect addressed by the recall and settlement. On 11/28/2025 I dropped the vehicle at group 1 Hyundai southwest houston (10301 southwest fwy, houston, TX 77074) for diagnosis and repair under the lifetime warranty. The dealership confirmed bearing failure but refused to repair, stating the vehicle is “not eligible” because the free campaign 953 knock-sensor software update was never performed. No owner (current or prior) ever received any recall notice or settlement notice despite Hyundai’s legal duty to notify all registered owners. On 12/04/2025, service advisor tevin told me to remove the car by Friday or face storage fees and possible lien sale. To avoid unlawful charges for a known safety defect, I paid $192. 70 out of pocket for aaa to tow the vehicle off the lot on 12/05/2025 (receipt available). Hyundai is using its own failure to provide notice as justification to deny legitimate lifetime-warranty claims and shift costs to consumers. The unrepaired vehicle remains a serious safety hazard (engine stall/fire risk) on the road. Requested action: investigate Hyundai motor America and its dealers for (1) systemic failure to notify owners of recall 953 and the theta ii settlement, (2) wrongful denial of lifetime-warranty engine repairs, and (3) imposing towing/storage fees on consumers for admitted safety defects. I have filed a claim with the settlement administrator and can provide receipts, recorded calls, and docs. Information redacted pursuant to the freedom of information a.

My 2013 Hyundai Sonata (VIN: [xxx] , 2. 4l theta ii gdi engine) is experiencing symptoms consistent with the known theta ii engine defects covered under prior NHTSA recalls (e. G. , 17v-226) and the related class action settlement for connecting rod bearing wear due to manufacturing debris restricting oil flow. The vehicle has begun exhibiting [describe your specific symptoms here, e. G. : "a loud metallic knocking/tapping noise from the engine that increases with rpm, especially during acceleration or at highway speeds; reduced engine power and hesitation; illumination of the check engine light and/or oil pressure warning light; excessive vibration; or sudden loss of power/stalling risk"]. These issues have [escalated/worsened over time or occurred suddenly while driving]. This poses a serious safety hazard because premature bearing wear can lead to complete engine seizure or stall without warning while the vehicle is in motion, potentially at highway speeds, resulting in loss of motive power, inability to maintain speed, or increased risk of collision, injury, or fatality. I have properly maintained the vehicle with regular oil changes using the recommended full synthetic oil [add if true: "and can provide service records showing no evidence of sludge or neglect"]. Despite submitting an appeal/claim under the Hyundai theta engine class action settlement (case number xxx), I received confirmation on December 30, 2025, promising a decision within 14 business days, but as of January 16, 2026, there has been no response or update despite follow-up attempts. This ongoing delay prevents me from obtaining the necessary inspection, repair, or replacement under the extended warranty/safety coverage, leaving the vehicle in a potentially unsafe condition. I am requesting that NHTSA review this as part of the pattern of theta ii engine failures in 2011-2014 Hyundai Sonatas, which have led to thousands of similar complaints, recalls, and investigations into untimely information redacted pursuant to the freedom of information ac.

My car was having an issue where it was losing all the coolant, causing my engine to overheat twice while driving down the highway. Unfortunately I couldn't find a leak anywhere and there was no fluid leaking in my garage. I lost an entire reservoir of coolant overnight. After taking my car to the dealership to get repaired, I was told that it was leaking my coolant into the exhaust system and burning it up. I was also told "it was a know issue, they had a bulletin from Hyundai on how to fix the problem, and Hyundai completely redesigned the part to stop the leak and it had to be special ordered. " I was without my car for a week and left with a $1300 bill as apparently it was not covered by my warranty. I have no idea how a known issue is happening so frequently that requires a nationwide bulletin and a part redesign, yet somehow is recalled. Especially considering it left me stranded on the side on the side of the highway in indiana during a snow storm but someone seriously needs to investigate it.

I bought this vehicle as a certified pre-owned from a Hyundai dealership on 09/10/2022 with 32,677 miles. Around 85,000 miles, it began burning an excessive amount of oil—about two quarts per month. Now, with approximately 101,000 miles, it still burns two quarts weekly, oil is being expelled from the muffler, and the exhaust has started to glow red. I have tried contacting Hyundai but have not received any response.

My car is blowing a large amount of white smoke due to the head gasket being cracked, I was quoted 2 grand to fix it. The car is not old enough to need a new head gasket, this is completely due to how the car manufactured and I have seen many other reports of this, there should be a recall and this should be fixed free of charge.

My 2015 Hyundai Sonata has a defective engine. The motor failed unexpectedly even though the car has low usage and has always been maintained properly. I was informed that many Hyundai engines from these years came with manufacturing issues, and mine appears to be one of them. I am requesting that Hyundai replace the engine or provide a proper solution since this defect is not due to misuse but a faulty motor that came from the manufacturer. I need this resolved as soon as possible because the car is not running at all.