My engine started leaking oil from the inside and all of a sudden my car started shaking out of nowhere
2018 Kia Optima
Owner reports · Recalls · Investigations
Similar to other model years
Owner complaints for the 2018 Kia Optima do not stand out strongly from the model-year median of 186.5.
About this comparison →How this year compares
Owner complaints by model year
Compare all Optima years →Counts vary with age, sales and reporting. They are not failure rates.
What owners reported most
All reported categories
Tap a category to read its complaints. One report may name several components.
When problems were reported
Mileage at the reported incident
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.
Engine complaints
131 reportsI have had this car in the shop multiple times for a engine light that kept coming on, they would reset and say they couldn't see anything wrong. Well my car died in Dec, it made a noise and would not accelerate. To avoid any further issues I parked it and had it towed to a dealership. They told me the catalytic converter had…
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I have had this car in the shop multiple times for a engine light that kept coming on, they would reset and say they couldn't see anything wrong. Well my car died in Dec, it made a noise and would not accelerate. To avoid any further issues I parked it and had it towed to a dealership. They told me the catalytic converter had come apart taking out the turbo and it would cost me $6k to fix. I decided to see if i could find parts cheaper, to find no one anywhere in the US or Canada has a converter for this car and it seems many dealerships have customers on waiting lists to get one, so I am now wondering if this is in fact a pretty large problem Kia is not addressing. I called Kia and got a very canned answer that parts were hard to come by right now and it could be up to 2 years to get the part. So I am now paying for a car i cannot drive and have no idea at this point if I will ever be able to drive it. i am hoping you are able to do some research to see if this is a bigger problem that nobody seems to be talking about. thank you
The contact owns a 2018 Kia Optima. The contact stated that the vehicle was experiencing abnormal oil consumption. The contact stated that on one occasion, 3 quarts of oil were added to the vehicle after less than 1,000 miles of driving. The vehicle was taken to the dealer who initiated an oil consumption test. The vehicle was t…
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The contact owns a 2018 Kia Optima. The contact stated that the vehicle was experiencing abnormal oil consumption. The contact stated that on one occasion, 3 quarts of oil were added to the vehicle after less than 1,000 miles of driving. The vehicle was taken to the dealer who initiated an oil consumption test. The vehicle was taken back to the dealer twice after 1,000 miles; however, upon returning to the dealer the third time, the dealer informed the contact that they could not complete the oil consumption test because the vehicle had been driven 1,200 miles. The dealer initiated another oil consumption test. The contact stated that the local dealer was 45 miles away from his residence, which made it difficult to complete the oil consumption test. The vehicle was not diagnosed or repaired. The manufacturer was notified of the failure, but no assistance was provided. The failure mileage was approximately 88,000.
1- My 2018 Kia Optima engine seized while driving on interstate 64 West -Had the car towed to a mechanic (J TEAM AUTO REPAIR) and was told me to contact kia because after replacing the spark plugs and coils and knock sensor there was still no compressing in cylinder 4. My life and safety was at risk when my engine blew out on …
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1- My 2018 Kia Optima engine seized while driving on interstate 64 West -Had the car towed to a mechanic (J TEAM AUTO REPAIR) and was told me to contact kia because after replacing the spark plugs and coils and knock sensor there was still no compressing in cylinder 4. My life and safety was at risk when my engine blew out on the interstate. When I went to Kia Dealership they confirmed that my VIN number was included in the recall and in the class action lawsuit. customer support told me since I wasn't the first owner of the car they weren't required to honor the recall -I asked why I was never informed they told me I bought the car as second owner my 60,000 warranty has expired and the extended warranty for engine doesn’t cover compression issues - its stated on the NHTSA website that they are required to send notices to all owners.When I contacted (Escalation Case specialist) with this information they said the extended warranty only covers the rod bearing connectors, and not compression. Completely contradicting the first call I had with another employee at Kia. Kia is deliberately keeping people in cars with engines that were manufactured improperly. I had the KSDS update-It takes more than reading engine codes to get to the bottom of things. Compression is part of the engine block. Prior to the Engine failure, my Kia Optima, was constantly burning oil.
Car burning excessive oil in engine. 2 quarts every 1,200 miles
The contact owns a 2018 Kia Optima. The contact stated that while driving at an undisclosed speed, the low-pressure engine oil warning light illuminated, and the vehicle stalled. The contact stated that the vehicle jerked and almost lost motive power however, the contact depressed the accelerator pedal and continued driving. Th…
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The contact owns a 2018 Kia Optima. The contact stated that while driving at an undisclosed speed, the low-pressure engine oil warning light illuminated, and the vehicle stalled. The contact stated that the vehicle jerked and almost lost motive power however, the contact depressed the accelerator pedal and continued driving. The contact stated that the failure had occurred on two occasions. The contact stated that the vehicle received an engine oil change; however, the failure reoccurred. The vehicle was not diagnosed or repaired by an independent mechanic or the dealer. The manufacturer was made aware of the failure. The failure mileage was approximately 57,000.
I took my vehicle to jenkins kia-ocala back in march and may of this year for my check engine light lashing on and off and acceleration issues, car shaking, and excessive oil spilling into my spark plugs. The 1st time I took my vehicle to this location i was told to "drive my vehicle until it no longer had any motor oil to "all…
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I took my vehicle to jenkins kia-ocala back in march and may of this year for my check engine light lashing on and off and acceleration issues, car shaking, and excessive oil spilling into my spark plugs. The 1st time I took my vehicle to this location i was told to "drive my vehicle until it no longer had any motor oil to "allow the motor to lock up" to then be approved to have my vehicle engine approved under the GDI recall". I expressed my great concerns to the employees about that statement and also reported the issue to bbb. I recently took my vehicle to kia jenkins Dec 8th for the very same reason only this time I showed them paperwork from a different certified mechanic who indicated that I have an internal engine issue. Kia then created a tech line case after seeing the paperwork showing i took my vehicle to a different shop. Over the course of holding my vehicle for over a week without any answers i was able to contact kia consumer affairs who offered to repair my vehicle under good will. Kia jenkins employee told me over the phone that my car will not be approved to be fixed due to the high mileage on my vehicle. I asked them what the miles has to do with my safety and the volunteer payment that kia consumer affairs is willing to pay as that is not a reason to deny a good will payment. The employee proceeded to state its not going to be approved and I expressed I felt this is due to my previous report to the bbb. 12.8.23 i received an email from Kia consumer affairs stating the good will case has been declined due to my vehicle not being "routinely maintained" according to the feedback from jenkins kia service department. I went to kia to pick up my vehicle. I proceeded to question what maintenance was recommended that they are claiming i did not complete as they never advised me of any issues with my car pertaining to their new list of things, they added on the invoice of things they claim i denied.
The contact owns a 2018 Kia Optima. The contact stated that while driving at an undisclosed speed, the vehicle stalled and jerked. The vehicle was towed to the dealer where it was purchased from. The contact was advised that the vehicle would be towed to a Kia dealer for service. The vehicle was towed to the Kia dealer and diagn…
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The contact owns a 2018 Kia Optima. The contact stated that while driving at an undisclosed speed, the vehicle stalled and jerked. The vehicle was towed to the dealer where it was purchased from. The contact was advised that the vehicle would be towed to a Kia dealer for service. The vehicle was towed to the Kia dealer and diagnosed with failed spark plugs. The contact was informed that the spark plugs needed to be replaced. The vehicle was repaired; however, the failure reoccurred. The vehicle was towed back to the Kia dealer and the contact was informed that the spark plugs were corroded due to oil consumption and the spark plugs needed to be replaced. The contact was also informed that the engine needed a combustion cleaning. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was unknown.
Was driving on the interstate. The only light on was the ABS light and the car started smoking. Had to come to a stop as they were sparks coming from out under the car through it into park at around 15 mph steel jumped out of the car and within a minute the car was fully engulfed in flames.
I purchased my 2018 Kia Optima directly from the dealership, brand new. I've had the vehicle since then and have followed all of the warranty guidelines and only went to them for oil changes & other maintenance issues. Since February 2023 I've noticed where i've been having oil loss, but no sign of an oil leak. When I first noti…
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I purchased my 2018 Kia Optima directly from the dealership, brand new. I've had the vehicle since then and have followed all of the warranty guidelines and only went to them for oil changes & other maintenance issues. Since February 2023 I've noticed where i've been having oil loss, but no sign of an oil leak. When I first noticed this, I would take a turn and my oil light would come on. I'd check the oil and it'd be low so I would refill my oil. However, this was happening 2 months after my last oil change which wasn't normal. I took the vehicle to Kia and they did an "Engine Consumption Test" where I had to drive for 1000 miles with a seal on the drain plug. After the 1000 miles, I came back and I was only 1/2 quart low. According to Kia it didn't meet the guidelines for engine replacement so they topped off my oil and I left. About 2 weeks after, my oil light came back on. I went back to Kia and spoke with the Shop Manager who stated I was 3 1/2 quarts low! He added oil to my engine and we did another round of the consumption test. When I came back in after that, I was 2 quarts low so that meant I qualified for a "Consumption Cleaning". They kept my vehicle overnight & I had to drive another 1000 miles. When I came in after my 1000 miles again I was only 1/2 quart low and therefore Kia said there wasn't an issue. I've reached out to multiple auto repair shops who state it is a Kia problem, that the engine is using it and processing it out of the exhaust. I don't know what else I have to do in order for Kia to honor the 20 year, 200k warranty. I have all documentation for all of my oil changes and from the consumption tests also.
Official recalls
223V594000 · Latches/locks/linkages:trunk Lid:latch
Aug 24, 2023
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.
18V161000 · Hybrid Propulsion System
Mar 8, 2018
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
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.
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