NHTSA owner reports · September 18, 2026 snapshot.
What owners actually said
372 reports117,000 miles · Aug 29, 2025
Engine
The contact owns a 2018 Hyundai Sonata. The contact stated that while driving approximately 60 MPH, the vehicle shuddered before losing automotive power. The check engine warning light was illuminated. The vehicle was taken to a local dealer, where it was diagnosed and determined that the engine and NOx sensor needed to be repla…
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The contact owns a 2018 Hyundai Sonata. The contact stated that while driving approximately 60 MPH, the vehicle shuddered before losing automotive power. The check engine warning light was illuminated. The vehicle was taken to a local dealer, where it was diagnosed and determined that the engine and NOx sensor needed to be replaced. The vehicle was repaired; however, the failure reoccurred. The vehicle was taken back to the same local dealer on several occasions for the repair; however, the failure reoccurred. The manufacturer was not made aware of the failure. The failure mileage was approximately 117,000.
NHTSA ODI #11683957
Mileage unknown · Aug 29, 2025
Exterior Lighting
Back up lights. The lights constantly burn out causing the harness light holder to burn out. The lights will not come on even after replacing fuse and lights There are not back lights to warn patrons on the road for turning or stopping Yes it was taken to a dealership No it has not been inspected my either , but there is a …
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Back up lights. The lights constantly burn out causing the harness light holder to burn out. The lights will not come on even after replacing fuse and lights There are not back lights to warn patrons on the road for turning or stopping Yes it was taken to a dealership No it has not been inspected my either , but there is a recall on models of the same car but years 2011-2014 No there were no warnings , someone told me they were out
NHTSA ODI #11683921
Mileage unknown · Aug 24, 2025
Engine
My 2018 Sonata has had an oil consumption problem since 2023. We initially thought it was the oil change garage issues. Had an oil consumption study conducted by Hyundai between July -September 2024. We were replacing 1,0 -1.5 qt oil every 700 - 1,300 miles. After the study, Hyundai told me I did not have an oil consumption prob…
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My 2018 Sonata has had an oil consumption problem since 2023. We initially thought it was the oil change garage issues. Had an oil consumption study conducted by Hyundai between July -September 2024. We were replacing 1,0 -1.5 qt oil every 700 - 1,300 miles. After the study, Hyundai told me I did not have an oil consumption problem. (Seriously?!?!) We had to replace the starter and now the spark plugs. Photo enclosed of how burnt the spark plugs were. Our mechanic was so mad that Hyundai was not honoring their warranty but allowing my engine and connected parts to just burn up. Hyundai told me to come in for another check tomorrow, 8/25/25. I called the Hyundai Consumer line on 8/18/25 (4th new case number in 13 months) and the person who answered the phone asked if I contacted a lawyer. I asked her if I needed to contact a ? I’ve been reading online about this problem today and found information about NHTSA and decided to file a complaint. This is dangerous because when the engine blows, I may be accelerating on the interstate and merging. That could be a fatal problem with this car. Traveling on the interstate on 8/10/2025 my Sonata stuttered and hesitated upon acceleration. We took back roads and limped home. My mechanic replaced the severely burnt spark plugs and told us our very nice car would be worthless soon if Hyundai did not fix this oil consumption problem. He called our Hyundai dealer on our behalf.
NHTSA ODI #11682710
Mileage unknown · Aug 18, 2025
Electrical SystemEngine
I first noticed that my vehicle was consuming an excessive amount of motor oil, with the oil change light coming on every 1,500–2,000 miles. I routinely had to add oil between changes to keep it running. On May 30th, while driving on surface roads, I heard clanking noises from the engine. When accelerating, the vehicle clanked …
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I first noticed that my vehicle was consuming an excessive amount of motor oil, with the oil change light coming on every 1,500–2,000 miles. I routinely had to add oil between changes to keep it running. On May 30th, while driving on surface roads, I heard clanking noises from the engine. When accelerating, the vehicle clanked heavily, and then went into “limp mode,” limiting acceleration to about 10 MPH before struggling up to 30 MPH. I added oil, but a local shop diagnosed it with code P1326 (knock sensor) and advised that Hyundai engines are prone to failure around 100,000 miles and that I should take it to the dealer for warranty evaluation. I contacted Graham Hyundai, who told me they could not see the vehicle until July 1st and that I would be responsible for towing. I dropped the vehicle off on July 1st, but it was not inspected until July 8th or 9th. I was later told Hyundai was being consulted. Around July 15th–16th, the dealership informed me that I would need $1,500 in repairs. They stated the engine had passed the Hyundai Bearing Clearance Test (a $350 charge) and that Hyundai required me to pay for an ECU “KSD logic” upgrade ($175). They also stated the engine valve cover was leaking, requiring new spark plugs, for a total of $532. Additional charges included an oil change and other shop fees and taxes. After repairs, I was instructed to drive 1,000 miles and then return for an oil consumption test. After approximately 1,000 miles and four weeks, the dipstick check showed the vehicle had consumed nearly all of its oil. I was then told I now need a combustion chamber cleaning, costing approximately $850 and requiring three days in the shop. Given the oil consumption issues, repeated engine warnings, limp mode incident, and the significant costs already incurred for testing and required upgrades, I am requesting that my engine be replaced under warranty and that all fees I have already paid be reimbursed. Rather than keep paying for work.
NHTSA ODI #11681369
Mileage unknown · Aug 17, 2025
Structure
The paint has been chipping from the hood and top.
NHTSA ODI #11681198
Mileage unknown · Aug 16, 2025
Forward Collision AvoidanceService Brakes
About a year and half ago, a lot of my engine trouble lights turned on while driving. It was sleeting at that time when the lights turned on and they're still on today. I paid to have the Hyundai dealer to check it out soon after the trouble lights first turned on. They diagnosed the problem as a faulty HECU. I would have had…
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About a year and half ago, a lot of my engine trouble lights turned on while driving. It was sleeting at that time when the lights turned on and they're still on today. I paid to have the Hyundai dealer to check it out soon after the trouble lights first turned on. They diagnosed the problem as a faulty HECU. I would have had them replace this, but they estimated it would cost about $3800 to fix. This HECU malfunction is causing the following issues: ABS does not work, traction control does not work, forward collision prevention does not work, brake auto hold does not work, cruise control does not work probably because it can't auto brake any more. I've had some scary times driving and trying to stop when the roads have been wet or snowy.
NHTSA ODI #11681116
Mileage unknown · Aug 15, 2025
Engine
Component or system that failed or malfunctioned: The 2.4L Theta II engine in my 2018 Hyundai Sonata is consuming an excessive and unsafe amount of engine oil—approximately 1 quart every 750–1000 miles. The engine has not seized or failed yet, but the oil consumption is abnormal and dangerous. The engine is available for inspect…
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Component or system that failed or malfunctioned: The 2.4L Theta II engine in my 2018 Hyundai Sonata is consuming an excessive and unsafe amount of engine oil—approximately 1 quart every 750–1000 miles. The engine has not seized or failed yet, but the oil consumption is abnormal and dangerous. The engine is available for inspection upon request. Safety risk: This oil consumption issue poses a significant safety risk. If the engine runs out of oil unexpectedly, it could lead to catastrophic engine failure and sudden loss of power while driving—potentially causing a serious accident. The lack of warning or engine light prior to dangerously low oil levels increases the risk. Reproduction/confirmation: The issue has been reproduced and documented by a certified Hyundai dealer through an oil consumption test. However, despite confirming the problem, Hyundai has refused to cover the repair. Inspection history: The vehicle has been inspected by a Hyundai dealership. No other independent agencies (e.g., insurance or police) have inspected it. Warning lamps or messages: No warning lamps appeared before the engine oil was found to be dangerously low. There were no check engine lights or oil pressure warnings prior to discovering the oil consumption issue. Other key information: Hyundai refuses to cover the repair due to the fact that I am not the original owner—even though the original Powertrain warranty would have covered the issue if I were. Hyundai arbitrarily reduces the powertrain warranty to 5 years/60,000 miles for secondary owners, despite the safety risks being identical regardless of ownership. Furthermore, this exact engine has been the subject of multiple lawsuits and class actions due to excessive oil consumption, connecting rod bearing failure, and engine seizure. Hyundai has acknowledged the defect in various settlements but continues to deny coverage for affected owners like me.
NHTSA ODI #11680962
Mileage unknown · Aug 11, 2025
EnginePower Train
Engine failure. Definitely a safety issue, check engine light flashing, limited engine power. Wouldn’t accelerate. Dealer inspected, there is a nationwide recall and class action lawsuits and they won’t replace even though it’s under warranty. False information saying maintenance neglect on my part. That is FALSE. Known failu…
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Engine failure. Definitely a safety issue, check engine light flashing, limited engine power. Wouldn’t accelerate. Dealer inspected, there is a nationwide recall and class action lawsuits and they won’t replace even though it’s under warranty. False information saying maintenance neglect on my part. That is FALSE. Known failure and oil consumption. Rod bearing failure.
NHTSA ODI #11679941
99,000 miles · Aug 7, 2025
Engine And Engine Cooling
The contact owns a 2018 Hyundai Sonata. The contact stated that after starting the vehicle, the engine oil warning light illuminated intermittently. The contact pulled over to check the engine oil level and discovered that there was no oil in the engine. The vehicle was taken to Midas, and engine oil was added. The vehicle was l…
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The contact owns a 2018 Hyundai Sonata. The contact stated that after starting the vehicle, the engine oil warning light illuminated intermittently. The contact pulled over to check the engine oil level and discovered that there was no oil in the engine. The vehicle was taken to Midas, and engine oil was added. The vehicle was later taken to another Midas, who found a crack in the engine oil pan. The vehicle was then taken to the dealer, who informed the contact that Midas had overtightened the oil pan during an oil change, so the warranty to repair the vehicle would not be honored. The vehicle was taken back to Midas, and the engine oil pan was replaced. The contact stated that he was currently in litigation with the dealer and the manufacturer. The manufacturer was made aware of the failure. The failure mileage was approximately 99,000. The VIN was unavailable.
NHTSA ODI #11679114
Mileage unknown · Aug 7, 2025
Fuel/propulsion System
The fuel pump filter housing is the cause of the malfunction, it is available for inspection upon request. When I am driving I intermittently lose fuel delivery altogether and my car comes to a halt for a second until I press on the gas pedal to get the car going again, this puts myself and other people in danger if my car ran…
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The fuel pump filter housing is the cause of the malfunction, it is available for inspection upon request. When I am driving I intermittently lose fuel delivery altogether and my car comes to a halt for a second until I press on the gas pedal to get the car going again, this puts myself and other people in danger if my car randomly stops while I am driving around others and causes crash risk. An independent service center ran a diagnostic and stated it was the fuel pump filter housing. It has not been inspected by the manufacturer, police, or insurance reps. But it has been inspected by the service center near me. An engine code was produced that pointed to the gas cap, but the gas cap was fine, which indicates fuel delivery issues. There was also shaking during acceleration prior to the incident happening. My VIN does not fall under the current extended warranty, but the issues are identical to the issues of the VINs that do fall under the extended warranty.
NHTSA ODI #11679080
NHTSA investigations
2DP22003 · Loss Of Motive Power
Opened Sep 12, 2022 · Closed Dec 12, 2023
Status: closed (inferred from source dates) · Engine
The National Highway Traffic Safety Administration (NHTSA) received a letter dated July 13, 2022, petitioning the Agency to initiate a safety defect investigation into loss of motive power allegations attributed to oil drain pan assembly failures on certain Hyundai Motor America, Inc. and Kia America, Inc. vehicles spanning Model Years (MY) 2005-2021. The Petitioners cited examples of complaints indicating that the subject vehicles were experiencing rapid loss of engine oil due to oil drain plug back outs, resulting in loss of motive power and/or catastrophic engine damage. Additional complaints were provided which alleged that the oil drain pans lack sufficient structural integrity and are susceptible to cracking. The petition itself can be reviewed at NHTSA.gov under ODI number 11481745. On September 12, 2022, the Office of Defects Investigation (ODI) opened Defect Petition (DP22-003) to evaluate the Petitioners’ request. The Petitioners have provided additional complaints within four supplemental letters dated January 31, 2023, March 21, 2023, May 23, 2023, and August 4, 2023. ODI’s evaluation included the review and analysis of the complaints and supporting information submitted by the Petitioners, as well as additional complaints submitted directly to NHTSA which referenced either the oil drain plug or a crack in the oil pan. After reviewing the available data, ODI has not identified evidence that would support opening a defect investigation into the oil drain pan assemblies of the subject vehicles. Based on a review of the available information, a loss of motive power resulting from an oil drain plug back out has not occurred between the initial sale of a vehicle and the completion of its first oil change. If during an oil change service, a technician fails to remove the existing drain plug gasket before installing a new gasket, it is likely that a proper seal between the drain plug and the oil pan will not be made. An improper seal between the drain plug and oil pan could lead to the backing out on the drain plug, resulting in the sudden loss of oil while driving. Additionally, the provided examples of oil pan cracks were localized to the immediate vicinity of the oil drain plug and/or appeared to be the result of direct-contact with a tool during servicing. There is no information to support that a vehicle-based defect exists relating to the oil pan assembly, and instead the documented incidents are related to the failure to follow the proper maintenance procedures during oil change service. In October 2023, Hyundai published a Technical Service Bulletin (TSB) that provided detailed instructions for oil change service on its gasoline powered vehicles, specifically highlighting the need to remove and replace the existing drain plug gasket prior to reinstalling the drain plug. After a thorough review of the material submitted by the petitioner, the information already in NHTSA's possession, and the potential risks to motor vehicle safety implicated by the petitioners' allegations, NHTSA does not believe that a formal investigation is warranted. Therefore, the petition is denied. A Federal Register Notice (FRN) further detailing NHTSA’s reasons for denial of the petition will be published. The reference numbers for the complaints to NHTSA cited by the petitioner can be found in the petition submission documents in the public file for DP22-003. To review those complaints and the additional complaints ODI added to its evaluation which are cited in the Closing Resume ODI Report Identification Number document, go to NHTSA.gov.
EA19001 · Electrical Overstress
Opened Apr 19, 2019 · Closed Sep 19, 2024
Status: closed (inferred from source dates) · Air Bags: Air Bag/restraint Control Module
The Office of Defects Investigation (ODI) opened this investigation to determine if the failure of airbags to deploy during severe crashes, in certain vehicles, was the result of a safety related defect. During the investigation a complex failure was studied that can result in non-deployment of subject vehicle air bags and other restraint system devices in severe crash events. The subject vehicles may be equipped with an airbag control unit (ACU) for the supplemental restraint system (SRS) Electronic Control Unit (ECU) manufactured by ZF-TRW. The ECU receives signals from crash sensors mounted in the vehicle and deploys the vehicle air bags and seat belt pretensioners in accordance with manufacturer design specifications. The ECU in the subject vehicles contains a model DS84 application-specific integrated circuit (ASIC) which controls the communication of the crash sensor signal, firing commands (i.e., when to deploy the airbag(s) and/or pretensioners), and fault information (e.g., diagnostic trouble codes). In September 2016, FCA announced recall 16V-668 for certain model year (MY) 2010 to 2014 Chrysler, Dodge and Jeep products manufactured with the subject ZF-TRW ACU. In this recall, FCA discussed an EOS condition that resulted in a failure of the subject DS84 ASIC, which caused air bag non-deployment. FCA noted that the defect condition had only been observed in vehicles equipped with sensor harnessing routed across the front of the vehicle. Other FCA vehicles that also used the subject ACU, but were not equipped with cross-car harnessing, had not experienced EOS failures, despite similar time in service. During the course of this investigation, ODI sent two separate Information Request (IR) letters to six vehicle manufactures (including FCA, Hyundai, Honda, Kia, Mitsubishi, and Toyota) and one IR letter to ZF-TRW. These IR letters resulted in ODI receiving comprehensive data from these manufacturers and suppliers. Studies of this data found that the DS84 ASIC does not have sufficient protection against negative electrical transients or electrical overstress (“EOS”) that can be generated in certain severe crashes. An electrical transient occurs when the electrical power supplied to a circuit changes momentarily over a short duration of time. In these severe crash cases, the crash sensors and other powered wiring can be damaged and short circuited so as to create a negative electrical transient of sufficient intensity and duration (that are outside the vehicle manufacturer's specification) to damage the ASIC before the restraint device deployment signal is received by the SRS ECU. This damaged signal can lead to incomplete or nondeployment of the air bags and/or pretensioners. Airbag non-deployment and/or lack of pretensioner operation can increase the risk or severity of injury in a crash.A total of 8 fatalities and 14 injuries were associated with known EOS events. The common element in all investigated manufacturers vehicles is the SRS ECU containing a DS84 ASIC manufactured by ZF-TRW. The risk associated with the ASIC is equally shared among all OEMS involved in the investigation. The actual real-world risk can be mitigated by other factors which were assessed by ODI during this investigation. The first mitigating factor involves protections built into the ACU design which protect the DS84 ASIC from damage. There are multiple strategies and levels of protection employed by different OEMs that provide effective EOS mitigation. The two most common strategies at the ACU level are circuit protection diodes on the remote senor signal lines, and current limiting resistors that protect critical components. The second mitigating factor is found at the vehicle level and involves the location and routing of the wires leading from the crash sensors to the SRS ECU. If the wires are well protected in a crash and are not routed with other power wires carrying large currents, the risk for an EOS event is significantly reduced or eliminated. These design specific factors combine to produce a spectrum of risk for the vehicles equipped with ACUs using the DS84 ASIC. Given the many of years of field exposure, it is possible to divide the subject population into two groups; vehicles which have experienced EOS events, and vehicles which have not experienced EOS field events. Four of the six OEMs involved in this investigation have experienced EOS field events on at least one of their models equipped with a DS84 ASIC. All vehicle models (including the Toyota models identified in the Failure Report Summary of the opening resume for this investigation) with field events have been recalled. In an abundance of caution, ODI kept this investigation open five years to monitor field performance and did not identify any field events on vehicles not included in existing safety recalls. Given the spectrum of risk identified in this investigation and that all vehicles with a demonstrated unreasonable risk have been recalled, ODI is closing this investigation. ODI is closing this investigation with the following manufacturer safety recalls: 16V-668, 18E-043, 18V-137, 18V-363, and 20V-024. With the recall actions taken by the subject vehicle and equipment manufacturers, this investigation is closed. The closing of this investigation does not constitute a finding by NHTSA that a safety-related defect does not exists on other model or model year vehicles outside of the recall scopes. The agency reserves the right to take further action if warranted by the circumstances.