2019 Hyundai Sonata

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.

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.

The contact owns a 2019 Hyundai Sonata. The contact stated that while driving 55 MPH, the check engine warning light illuminated, and the vehicle went into LIMP Mode. The contact stated that the vehicle failed to accelerate above 58 MPH. The contact retrieved DTC: P1326 (Knock Sensor Detection System) at O'Reilly Auto Parts and stated that the knock sensor had previously been replaced. The failure mileage was approximately 90,000.

NHTSA ID

11763290

Incident

Sep 10, 2026

Mileage

90,000 mi

The low-pressure fuel pump module assembly, located directly beneath the rear passenger seat cushion, experienced a plastic housing failure. A stress fracture on the upper plastic fuel outlet nipple caused raw liquid gasoline to actively weep and pool on top of the module inside the passenger cabin. This component is retained and available for inspection upon request. RISK TO SAFETY: Raw liquid gasoline pooling inside the interior passenger compartment creates an severe, immediate fire and explosion hazard. Additionally, vehicle occupants were exposed to toxic fuel vapors while driving. INSPECTION & DEALER CONFIRMATION: An authorized Hyundai dealership inspected the vehicle and confirmed raw fuel leaking at the top of the fuel pump module assembly. This exact module had previously been removed and disassembled during a 2024 manufacturer recall service to replace the internal fuel filter and tank seal. Stress applied to the plastic fittings during that recall service appears to have caused the plastic top-hat to fracture over time under line pressure. Hyundai Corporate was notified of the safety hazard and prior recall history, but refused assistance. WARNING SYMPTOMS: The failure began with a strong, persistent fuel odor inside the vehicle cabin. No dashboard warning lights, check engine lights, or diagnostic trouble codes (DTCs) triggered prior to or during the failure. SUMMARY: A stress-fractured plastic fuel pump housing allowed raw fuel to pool in the passenger cabin following a prior manufacturer recall repair involving the disassembly of the same component.

NHTSA ID

11762354

Incident

Jul 1, 2026

The contact owns a 2019 Hyundai Sonata. The contact stated that while driving at an undisclosed speed, the vehicle experienced severe overheating and excessive oil consumption. The contact also stated that there was a misfire in the engine even though the spark plugs and ignition coils were replaced. Due to the failure, the vehicle could not be driven with the air conditioning activated. Additionally, the engine was knocking and shaking abnormally, causing an oil leak and a smoke odor due to the oil burning. The vehicle was taken to a dealer, where an engine replacement was recommended. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was 140,000.

NHTSA ID

11757693

Incident

Jul 1, 2026

Mileage

140,000 mi

The oil is low, went to get looked at by another mechanic besides Dealer cause they want to hit you over the head with prices. Was told car burning oil. Took to dealer for Oil Consumption Test. Had to pay for oil change. Came back a little before 1,000 miles and car failed. They charging me 900.00 for next step because I can’t find ALL the oil changes. I just don’t get it, if this is a known issue with this model engine why do I have to pay.

NHTSA ID

11757665

Incident

Jul 7, 2026

On January 26, 2026, my 2019 Hyundai Sonata SEL suddenly became inoperable overnight. The vehicle had been operating normally with no warning signs—no check-engine or oil-pressure light, abnormal engine noise, overheating, loss of power, or other indication of an impending failure. The following morning, the engine would not start. The vehicle was towed to an independent mechanic on January 28, 2026, who determined that the engine was locked/seized. On February 11, 2026, it was towed to Wayne Hyundai for further diagnosis. The vehicle had only 51,533 miles and had received Hyundai’s Knock Sensor Detection System (KSDS) update. Hyundai denied warranty coverage, citing engine sludge, despite my providing a complete service history after resubmiting the missing receipts I had previously misplaced. My primary concern is safety, not the warranty dispute. A sudden engine seizure without warning could cause an unexpected loss of propulsion or create a dangerous situation if the engine fails while the vehicle is being driven. This concerns me because Hyundai Theta II engines have previously been associated with engine seizure and stalling, including issues addressed through The Hyundai Theta II Engine Settlement: and subsequent litigation involving certain 2019 Sonata vehicles. I respectfully request that NHTSA investigate whether a continuing or insufficiently addressed engine defect exists in affected 2019 Hyundai Sonata vehicles, particularly sudden engine seizure/no-start failures occurring without warning. I also ask NHTSA to examine whether existing recalls, campaigns, software updates, warranty extensions, and other remedies adequately protect owners when an engine fails suddenly before the KSDS system provides a warning.

NHTSA ID

11756831

Incident

Jan 26, 2026

Vehicle stalled in traffic due to recall defect. Manufacturer recall remedy is delayed beyond reasonable timeframe, creating ongoing safety exposure.

NHTSA ID

11755086

Incident

Jul 31, 2026

The contact owns a 2019 Hyundai Sonata. The contact stated that while driving at an undisclosed speed, smoke started coming from the hood and the vehicle was pulled over into a parking space. While opening the hood, the contact saw that fire was coming from the top of the engine. The contact stated that the fire consumed the front of the vehicle, including the windshield and the dashboard. The smoke coming from the vehicle was dark gray and turned black afterwards. The contact called 911, and the Fire Department was able to extinguish the fire. There were no injuries reported. A vehicle parked next to the vehicle was damaged by the flames. The contact's vehicle was not inspected or officially deemed a total loss. The vehicle was towed to an independent mechanic where an oil change had been performed prior to the failure. The mechanic stated that there might have been a high-pressure fuel valve on top of the engine that possibly caused a gas leak, which started the fire. The vehicle was not diagnosed or repaired. The dealer was not contacted. The manufacturer was not made aware of the failure. The failure mileage was 172,000.

NHTSA ID

11752343

Incident

Jul 16, 2026

Mileage

172,000 mi

Driver's side seatbelt retraction mechanism failed without warning. Intentionally brought car to dealer ASAP since it was close to 100,000 miles pointed out. This was serious safety defect dealer refused to repair under warranty.

NHTSA ID

11750832

Incident

Jul 10, 2026

Certain vehicles may exhibit excessive paint peeling or bubbling of the primer/paint film on the exterior metal body panels: hood, fender(s), roof, door(s), quarter panel(s), and tailgate/trunk. This warranty extension only applies to factory-applied paint and does not cover collision-related paint repairs or vehicles with a salvaged title. Hyundai is extending the warranty coverage for certain white paint colors under these conditions from 3 years and 36,000 miles, to 10 years with unlimited miles from the date of original retail delivery or date of first use, and is valid for original and subsequent owners.

Certain Santa Fe (TMA), Santa Fe Sport (AN), Sonata (LFA), and Tucson (TL) vehicles equipped with Theta II engines may exhibit elevated engine-out emissions. The California Air Resources Board has determined that these vehicles may be releasing air pollutants which exceed Federal and California standards.

Certain Santa Fe (TMA), Santa Fe Sport (AN), Sonata (LFA), and Tucson (TL) vehicles equipped with Theta II engines may exhibit elevated engine-out emissions. This bulletin provides instructions for updating the Engine Control Module (ECM) to address this condition.

Following completion of Service Campaign 9C2 (Theta II Emissions Improvement), certain vehicles may exhibit a brief hesitation or rough shifting condition during cold start operation. If present, this condition is expected to occur only within approximately the first 1-3 minutes after engine start, while the catalyst is reaching its normal operating temperature.

Following completion of Service Campaign 9C2 (Theta II Emissions Improvement), certain vehicles may exhibit a brief hesitation or rough shifting condition during cold start operation. If present, this condition is expected to occur only within approximately the first 1-3 minutes after engine start, while the catalyst is reaching its normal operating temperature.

Some Hyundai vehicles with exterior white paint may exhibit peeling or bubbling on metal body panels: hood, fender(s), roof, door(s), quarter panel(s), and tailgate/trunk. The paint warranty coverage for affected vehicles has been extended to 10 years/unlimited miles from the date of original retail delivery or date of first use and is valid for original and subsequent owners.