Tap a category to read its complaints. One report may name several components.
When problems were reported
Mileage at the reported incident
260–25K
1225–50K
1350–75K
975–100K
13100–150K
0150K+
73 reports with mileage · 159 unknown
NHTSA’s mileage field refers to the reported incident, not necessarily the filing date. This shows report counts, not the likelihood of a failure.
What to inspect
Issues worth paying extra attention to based on owner reports.
Engine. Review the 131 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
Electrical System. Review the 33 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
Power Train. Review the 18 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
NHTSA owner reports · September 18, 2026 snapshot.
10 crash reports10 fire reports7 injury reports
What owners actually said
232 reports
Mileage unknown · Jul 10, 2023
Visibility/wiper
Was driving vehicle on freeway, around 65 mph, smooth road, no bumps, no indication of any road debris and suddenly heard a loud cracking/exploding noise which was extremely startling. After hearing some outside wind noise and the sound of glass pieces rattling, I realized that the glass panoramic sunroof must have broken someh…
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Was driving vehicle on freeway, around 65 mph, smooth road, no bumps, no indication of any road debris and suddenly heard a loud cracking/exploding noise which was extremely startling. After hearing some outside wind noise and the sound of glass pieces rattling, I realized that the glass panoramic sunroof must have broken somehow. Luckily I had the interior fabric shade closed, so no glass pieces entered the cabin to injure anyone. After getting out of the car, I could see around a 12 inch diameter hole in the sunroof glass. The remaining glass that was still attached was full of cracks. I have created a case with Kia Consumer Affairs and waiting to hear back from them. The vehicle has not received any outside inspection as of yet for this incident. There was no prior warning to this issue, no creaking noises or visible cracks.
NHTSA ODI #11531463
Mileage unknown · Jul 3, 2023
Engine
Engine failure just like all the other optima’s.
NHTSA ODI #11530105
Mileage unknown · Jun 21, 2023
Engine
MY ENGINE STARTED MAKING A HORRIBLE NOISE AND JUMPIMG. THE OIL WAS JUST CHANGED AND IS FINE. HAVING TO REPLACE ENGINE AND ONLY HAD CAR 2 MONTHS
NHTSA ODI #11528200
Mileage unknown · Jun 19, 2023
EngineVehicle Speed Control
Knock sensor detection system. Driving and all the sudden felt like it hard down shifted… car behind me almost hit me. Engine light started flashing so I pulled into autozone and plugged it in and got the knock sensor code. It’s had oil consumptions issues for a while. It’s so dangerous to drive with limited power and speed
NHTSA ODI #11527753
Mileage unknown · Jun 18, 2023
Engine
I purchased this vehicle used in April 2023 with 3,000 to go prior to another oil change. I returned home from a trip and the oil light would come on only while turning or braking. When checking the oil there was no oil in the motor. The reservoir was filled and two weeks in the engine is low on oil again. There are no leaks. Th…
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I purchased this vehicle used in April 2023 with 3,000 to go prior to another oil change. I returned home from a trip and the oil light would come on only while turning or braking. When checking the oil there was no oil in the motor. The reservoir was filled and two weeks in the engine is low on oil again. There are no leaks. The car jerks at lights as if it wants to stall out. I feel unsafe driving this car.
NHTSA ODI #11527580
68,000 miles · Jun 6, 2023
EngineFuel/propulsion SystemSteering
High injector fuel pump top engine mount went out at 68000 miles. It caused the vehicle to stall and lose power and basically cut the car off while driving.
NHTSA ODI #11525549
Mileage unknown · Jun 1, 2023
Power TrainUnknown Or OtherVehicle Speed Control
Ever since I got my car I’ve had black oil since the start . Second my car breaks on its own at times 3rd my car system keep breaking down as the sparks leaking in some where has this issue since bought it 2 years ago low miles
NHTSA ODI #11524862
Mileage unknown · May 31, 2023
EngineFuel/propulsion SystemVehicle Speed Control
-Knock Sensor Detection System - ECU Logic Improvement - I Was driving with my infant son in the backseat. I was going 70 mph when my car started rapidly losing speed. This happened again with just myself after receiving the car from mechanic. There was heavy traffic and I had to swerve to avoid being hit by an 18-wheeler. - I…
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-Knock Sensor Detection System - ECU Logic Improvement - I Was driving with my infant son in the backseat. I was going 70 mph when my car started rapidly losing speed. This happened again with just myself after receiving the car from mechanic. There was heavy traffic and I had to swerve to avoid being hit by an 18-wheeler. - I can see on the website where I received the car from, there is a recall for my exact make and model with the same code but they say there is no recall for my specific car. - The check engine light started flashing and Kia Systems starts talking.
NHTSA ODI #11524617
106,983 miles · May 29, 2023
EngineVehicle Speed Control
Car smoking white , and driving slow after I hit a pothole when it was raining hard.
NHTSA ODI #11524344
70,000 miles · May 17, 2023
Electrical SystemEngine
The contact owns a 2018 Kia Optima. The contact stated that the vehicle was sputtering while being started. The contact stated that the vehicle also sputtered while driving at various speeds, and while reversing. The check engine warning light was illuminated. The vehicle was taken to the dealer and the contact was informed that…
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The contact owns a 2018 Kia Optima. The contact stated that the vehicle was sputtering while being started. The contact stated that the vehicle also sputtered while driving at various speeds, and while reversing. The check engine warning light was illuminated. The vehicle was taken to the dealer and the contact was informed that oil was getting onto the spark plugs and ignition coils. The spark plugs and ignition coils were replaced; however, the failure persisted. The manufacturer was not made aware of the failure. The approximate failure mileage was 70,000.
Kia America, Inc. (Kia) is recalling certain 2016-2017 Rio, 2016-2018 Optima, 2017-2018 Optima Hybrid and Optima Plug-in Hybrid vehicles. The trunk latch base may crack, preventing the opening of the trunk from the inside. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 401, "Internal Trunk Release."
Consequence & remedy
Consequence: A person inside the trunk compartment may become trapped, increasing their risk of injury.
Remedy: Dealers will replace the trunk latch base subassembly, free of charge. Owner notification letters were mailed October 19, 2023. Owners may contact Kia customer service at 1-800-333-4542. Kia's number for this recall is SC278.
Kia Motors America (Kia) is recalling certain 2017-2018 Kia Optima hybrid vehicles. These vehicles are equipped with a Voltage Protection Device (VPD), designed to protect the high voltage battery module, that may activate inadvertently.
Consequence & remedy
Consequence: If the VPD activates while the vehicle is being operated in Electric Vehicle (EV) mode, there may be a loss of power, increasing the risk of a crash.
Remedy: Kia will notify owners, and dealers will remove the VPD switch and install two newly designed Battery Management Systems (BMS) that contain Overvoltage Protection Devices (OPDs), free of charge. The recall is expected to begin May 2018. Owners may contact Kia customer service at 1-800-333-4542. Kia's number for this recall is SC162.
Model-level recall history does not show whether a particular VIN is affected or has received a repair. Check a VIN with NHTSA ↗
NHTSA investigations
2
DP22003 · 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.
2018 Kia Optima Problems, Complaints & Recalls | Skip That Year