2016 Kia Optima

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) of the National Highway Traffic Safety Administration (NHTSA) received a petition letter dated October 10, 2021, requesting an investigation of possible defects in the electronic throttle control (ETC) system on certain Kia vehicles resulting in the opening of DP21-003. Accordingly, Model Year (MY) 2005-2016 Kia Optima/K5, MY 2006-2015 Kia Sorento, MY 2007-2016 Hyundai Elantra, MY 2007-2016 Hyundai Santa Fe, MY 2006-2015 Hyundai Sonatas are all part of the subject population. The petition was originally filed as a Vehicle Owner Questionnaire that can be reviewed at NHTSA.gov under reference (ODI) number 11439675.On November 12, 2021, ODI opened Defect Petition DP21-003 to evaluate the petitioner?s request. ODI performed trend analyses of the VOQs related to vehicle speed control issues for all the subject vehicles and found that none of the 52 Model/Model Year Hyundai/Kia vehicles demonstrated any actionable trend that warranted an investigation.Petitioners submitted 1119 VOQs and non-VOQ cases in which sudden uncommanded acceleration (SUA) or loss of motive power (LOMP) incidents were alleged.For the 1119 reports, 220 were incidents involving crashes, from which 69 subject Hyundai-Kia vehicles were inspected by Hyundai/Kia dealer technicians, Hyundai/Kia engineers, and/or third-party representatives.ODI found the inspections identified no vehicle defects related to the ETC system.Of the 220 crash-involved reports, 13 Event Data Recorder (EDR) records were downloaded successfully and 11 of those indicated driver error: (i.e.) pedal misapplication.A condition where the accelerator pedal is mistakenly applied instead of the brake pedal when the driver wants to stop the vehicle.In addition, ODI reviewed a scientific journal paper published in Forensic Science International in 2016 by Mr. Park et al ., as well as related test videos. ODI does not believe there is any evidence of uncontrollable SUA occurrences in any of the tests reviewed. NHTSA's Office of Vehicle Safety Compliance (OVSC) reviewed the allegations regarding the potential noncompliance with Federal Motor Vehicle Safety Standard No. 124.Based on the information provided, the Agency concludes there is insufficient information for us to determine if a possible non-compliance exists.Finally, both Hyundai and Kia informed ODI that all their vehicles manufactured after 2012 were equipped with an ETC management system, in which the engine speed will go to idle when the system sees signals from both the brake pedal and accelerator pedal at the same time; this is commonly known as the brake-throttle override system.After thoroughly assessing the material submitted by the petitioner, information already in NHTSA's possession, information submitted by Hyundai and Kia in response to an Information Request letter, and the potential risks to safety implicated by the petitioner's allegation, NHTSA does not believe that a formal investigation is warranted. After full consideration of appropriate factors, the petition is denied. A Federal Register Notice (FRN) further detailing NHTSA?s reasons for denial of the petition will be published.

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 engine assembly completely seized and the vehicle is currently stored at an independent repair shop . While traveling at high speed on Interstate 4 on July 24, 2026, the vehicle suffered a sudden, catastrophic loss of power and stalled in live traffic, creating an immediate threat of a high speed rear end collision. An independent service center officially confirmed the engine seizure after a dealership failed to perform an inspection during an eight hour wait, and no law enforcement or insurance inspections have occurred. Prior symptoms included severe, recurring oil loss requiring constant manual additions of oil between regular service intervals (most recently serviced in June 2026 at a kia dealership), and eventually the car completely shutoff on July24.

NHTSA ID

11754979

Incident

Jul 24, 2026

engine failure, i was driving home from work and i went to accelerate from 0 to 20 miles and the car hesitated and didn't want to move. I took the car to the dealer three days later and it was confirmed that i needed a new engine. I was told by the dealership i was outside of my warranty but i just found out that i was covered up to 120k miles. No lights came on at the time and there wasn't any prior warnings to this happening. I had just put oil into the car two days earlier as i know in between oil changes that i have to put oil into the car and or check the oil to see if it is low.

NHTSA ID

11753609

Incident

Sep 22, 2025

NHTSA Bulletin TSB BOD300 My KIA 2016 Optima Turbo has all four windows impacted by the defective gear. I've opened a case with KIA and it's case number 25563361. None of my windows roll up or down. This presents several very serious safety issues. The dealer has had my vehicle for over 2 weeks. Why has KIA not been forced to issue a recall on these defective gears?

NHTSA ID

11750007

Incident

Sep 15, 2025

Code was on and off for a cylinder 2 misfire was off at this point (intermittent misfire) ecl was off car stalled out at 3rpms while driving, tiny puff of smoke once came from between the air intake and the engine, and also no crank no start but car has power. I’ve kept up with the oil changes every 3000 miles car had fluids in it and nothing looked bad all 4 spark plugs were burnt and i replaced them and still no success.

NHTSA ID

11748217

Incident

Jul 1, 2026

I had just stopped at stop sign and I turned right. My speed was approximately 40 mph and there was a LOUD POP. I immediately hit the brakes and had NO BRAKES. I got car off road and smoke was already coming from under hood. It caught fire immediately and burned up. Total loss . About 6 months prior to it burning I had a good bit of front end work done on it with bearing issues. Also put a new set of tires at same time . The coils and plugs were changed often because it would misfire. I purchased car July 2025. All my documents were burnt also .

NHTSA ID

11747946

Incident

Apr 13, 2026

The contact owns a 2016 Kia Optima. The contact stated that while driving 10 MPH, the front driver’s and passenger’s side windows lowered unintendedly. Neither the dealer nor an independent was contacted. The vehicle was not taken to the dealer or an independent mechanic to be diagnosed. The rear driver’s and passenger’s side windows were replaced, and the vehicle was repaired. The manufacturer was notified of the failure but offered no assistance since the VIN was not under recall. The failure mileage was 107,000.

NHTSA ID

11745895

Incident

May 23, 2026

Mileage

107,000 mi

My 2016 Kia Optima equipped with the 2.4L DOHC I4 GDI engine began to experience progressive and severe oil consumption during the latter part of my ownership. The oil warning light began activating repeatedly, even after shortly getting the oil changed. Several certified mechanics and oil change service stations told me this was an ongoing issue with this car and engine and that there was nothing I could do but monitor it and keep it filled. At their instruction, I monitored and had it changed more frequently, often topping it off at the oil change station and at home when needed. Approximately 2 weeks after an oil change upon putting the car in reverse it started to shake uncontrollably. The car was towed to a mechanic who stated I needed an engine. I then towed it to an authorized Kia franchise dealership where the technician documented the oil consumption complaint, confirmed a Cylinder 2 misfire code, performed a borescope inspection, and found the Cylinder 2 exhaust valve burnt with a chunk missing. Engine replacement was recommended by the Kia dealership technician. Prior to my purchase, the engine had already been replaced at approximately 80,000 miles under recall-related circumstances. The replacement engine installed by a Kia dealership subsequently failed, exhibiting symptoms consistent with the documented widespread defect affecting the 2.4L DOHC I4 GDI engine in 2016 Kia Optima vehicles, including severe oil consumption, cylinder misfire, and catastrophic internal engine damage confirmed via borescope at a Kia franchise dealership. Kia America denied the claim based solely on mileage despite the damage being confirmed by their franchise technician. My vehicle became unsafe to drive due to this engine instability shortly after starting before becoming fully inoperable. My vehicle has been non-operational for approximately 5 months. Kia has not provided a substantive written determination despite a formal written demand submitted in March 2026.

NHTSA ID

11744531

Incident

Jan 10, 2026

the engine. I was at a stop sign when the car stop responding to me pressing the accelerator and would not go. Upon further inspection it was noted that my car had no oil in it. I am diligent in getting my oil changed every 3 months or 3,000 miles. My engine had "seized" and i am being advised to purchase a new engine or purchase a new car. While trying to get my car to acclerate i was almost hit 4 times in a matter of 10 mins.

NHTSA ID

11744474

Incident

Jun 15, 2026

TECHNICAL SERVICE BULLETIN: CUSTOMER SATISFACTION: THEFT DETERRENT IGNITION CYLINDER PROTECTOR AND DECAL INSTALLATION (CS2312) - This bulletin has been revised to include additional information. New/revised sections of this bulletin are indicated by a black bar in the margin area. This bulletin provides information to install a Theft Deterrent Ignition Cylinder Protector on certain 2010-2022MY Kia vehicles outlined on page 20, which may not have been equipped with an immobilizer and whose Integrated Body Control Unit (IBU) / Body Control Module (BCM) did receive the Anti-Theft Software Logic upgrade under CS2301/02/03/04/05/06/07/08/09 TSBs. In an effort to help prevent thefts of Kia vehicles, a protective cover will be permanently affixed to the ignition cylinder. This Theft Deterrent Ignition Cylinder Protector prevents the removal of the key lock cylinder thereby preventing access to the ignition tumbler.

VOLUNTARY EMISSIONS SERVICE CAMPAIGN: THETA II 2.4L GDI EMISSIONS: ECM LOGIC IMPROVEMENT (SC340 REVISION 5) - This bulletin has been revised to include additional information. New/revised sections of this bulletin are indicated by a black bar in the margin area. This bulletin provides information to upgrade the Electronic Control Module ‘ECM’ system software for certain 2016-2020MY Optima, 2016-2020MY Sorento, 2017-2022MY Sportage vehicles equipped with 2.4L Theta II engines listed in the table below. Kia has become aware that certain 2016-2022MY vehicles equipped with 2.4L Theta II engines may have engine calibrations that were not optimized for emissions standards under certain specific conditions. These calibrations may cause the vehicle to release air pollutants which exceed Federal and California standards. These standards were established to protect your health and welfare from the dangers of air pollution.

VOLUNTARY EMISSIONS SERVICE CAMPAIGN: OWNER NOTIFICATION (SC340 FLIGHT 104 ) - This document is the owner notification advising that Kia is conducting a Voluntary Emissions Service Campaign to improve the emissions software logic in the Electronic Control Module (ECM) for certain 2016-2020 MY Optima vehicles equipped with 2.4L Gas Direct Injection (GDI) engines to ensure compliance with emissions regulations.

TECHNICAL SERVICE BULLETIN: VOLUNTARY EMISSIONS SERVICE CAMPAIGN: THETA II 2.4L GDI EMISSION SECM LOGIC IMPROVEMENT (SC340 REV 4) - This bulletin has been revised to include additional information. New/revised sections of this bulletin are indicated by a black bar in the margin area. This bulletin provides information to upgrade the Electronic Control Module ‘ECM’ system software for certain 2016-2022MY vehicles equipped with 2.4L Theta II engines listed in the table below. Kia has become aware that certain 2016-2022MY vehicles equipped with 2.4L Theta II engines may have engine calibrations that were not optimized for emissions standards under certain specific conditions. These calibrations may cause the vehicle to release air pollutants which exceed Federal and California standards. These standards were established to protect your health and welfare from the dangers of air pollution.

TECHNICAL SERVICE BULLETIN: CUSTOMER SATISFACTION: THEFT DETERRENT IGNITION CYLINDER PROTECTOR AND DECAL INSTALLATION (CS2312) - This bulletin has been revised to include additional information. New/revised sections of this bulletin are indicated by a black bar in the margin area. This bulletin provides information to install a Theft Deterrent Ignition Cylinder Protector on certain 2010-2022MY Kia vehicles outlined on page 20, which may not have been equipped with an immobilizer and whole Integrated Body control Unit (IBU) / Body Control Module (BCM) did receive the Ant-Theft Software Logic upgrade under CS2301/02/03/04/05/06/07/08/09 TSBs. In an effort to help prevent thefts of Kia vehicles, a protective cover will be permanently affixed to the ignition cylinder. This Theft Deterrent Ignition Cylinder Protector prevents the removal of the key lock cylinder thereby preventing access to the ignition tumbler.

VOLUNTARY EMISSIONS SERVICE CAMPAIGN: OWNER NOTIFICATION (SC340 FLIGHT 103 / JF) - This document is the owner notification advising that Kia is conducting a Voluntary Emissions Service Campaign to improve the emissions software logic in the Electronic Control Module (ECM) for certain 2016-2020 MY Optima vehicles equipped with 2.4L Gas Direct Injection (GDI) engines to ensure compliance with emissions regulations.