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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.

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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.

10 crash reports10 fire reports7 injury reports

Engine And Engine Cooling complaints

14 reports
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Mileage unknown · Jul 22, 2026
Engine And Engine Cooling

See attached document for complaint.

NHTSA ODI #11752131

1,500 miles · Jun 23, 2026
Engine And Engine Cooling

The contact owns a 2018 Kia Optima. The contact stated that while driving at an undisclosed speed, there was an abnormal odor and a knocking sound coming from the engine. The vehicle was taken to the dealer; however, the dealer was unable to duplicate the issue. The vehicle was not repaired. The issue persisted. The contact stat…

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The contact owns a 2018 Kia Optima. The contact stated that while driving at an undisclosed speed, there was an abnormal odor and a knocking sound coming from the engine. The vehicle was taken to the dealer; however, the dealer was unable to duplicate the issue. The vehicle was not repaired. The issue persisted. The contact stated that the vehicle was later returned to the dealer to be repaired under a service campaign involving the engine control unit (ECU). Shortly after the vehicle was repaired, the ECU failure message was displayed. The vehicle subsequently became inoperable. The vehicle was not repaired. The manufacturer was notified of the issue. The approximate failure mileage was 1,500.

NHTSA ODI #11745997

121,000 miles · May 6, 2026
Engine And Engine CoolingLatches/locks/linkages

The contact owns a 2018 Kia Optima. The contact stated that while attempting to accelerate from a standing start the vehicle had experience sever jerking and hesitation. Also, the vehicle has experience oil consumption problems and the contact constantly added engine oil. The cause of the failures were not determine. Also, the …

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The contact owns a 2018 Kia Optima. The contact stated that while attempting to accelerate from a standing start the vehicle had experience sever jerking and hesitation. Also, the vehicle has experience oil consumption problems and the contact constantly added engine oil. The cause of the failures were not determine. Also, the hood latch had malfunctioned and the hood could not opened to add oil to the engine. The cause of the failures were not determined. The local dealer and manufacturer were notified of the failures but no assistance was offered. The failure mileage was 121,000.

NHTSA ODI #11736008

10,000 miles · Aug 18, 2025
Engine And Engine Cooling

The contact owns a 2018 Kia Optima. The contact stated that while driving at various speeds, the vehicle hesitated while depressing the accelerator pedal with the oil warning light flashing on the instrument panel. The contact's friend initially inspected the vehicle and discovered that the engine oil was empty. The vehicle was …

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The contact owns a 2018 Kia Optima. The contact stated that while driving at various speeds, the vehicle hesitated while depressing the accelerator pedal with the oil warning light flashing on the instrument panel. The contact's friend initially inspected the vehicle and discovered that the engine oil was empty. The vehicle was taken to a dealer where a diagnostic test was performed, and the mechanic discovered oil around the engine; however, the source of the leak was not discovered. The contact was informed that an engine valve was sealed and that the failure was repaired. Despite the repair, the failure persisted, and the oil light was frequently illuminated on the instrument panel. The engine oil level was checked and was extremely low. The dealer had not offered any additional assistance for the repair. The vehicle was not repaired. The contact made several attempts to reach the manufacturer but was unsuccessful. The failure mileage was approximately 10,000.

NHTSA ODI #11681328

109,000 miles · Mar 19, 2025
Engine And Engine Cooling

The contact owns a 2018 Kia Optima. The contact stated that while driving 65 MPH, the check engine warning light illuminated, and the vehicle shuddered and stalled. The contact was able to pull over to the side of the road. The vehicle was able to restart but was shuddering significantly. The vehicle was towed to the dealer, whe…

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The contact owns a 2018 Kia Optima. The contact stated that while driving 65 MPH, the check engine warning light illuminated, and the vehicle shuddered and stalled. The contact was able to pull over to the side of the road. The vehicle was able to restart but was shuddering significantly. The vehicle was towed to the dealer, where it was diagnosed with a fractured valve in cylinder #1. The dealer determined that the engine needed to be replaced. The vehicle was not repaired due to the cost. The manufacturer was notified of the failure and confirmed that the maintenance records of the vehicle were satisfactory; however, the manufacturer denied assistance and informed the contact that the failure was not a factory defect but was due to wear and tear. The failure mileage was approximately 109,000.

NHTSA ODI #11649251

106,000 miles · Dec 20, 2024
Engine And Engine Cooling

The contact owns a 2018 Kia Optima. The contact stated that while his daughter was driving at an undisclosed speed, the check engine warning light illuminated, and the vehicle went into LIMP Mode. The vehicle was towed to an independent mechanic, who related the failure to NHTSA Campaign Number: 17V224000 (Engine and Engine Cool…

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The contact owns a 2018 Kia Optima. The contact stated that while his daughter was driving at an undisclosed speed, the check engine warning light illuminated, and the vehicle went into LIMP Mode. The vehicle was towed to an independent mechanic, who related the failure to NHTSA Campaign Number: 17V224000 (Engine and Engine Cooling); however, the VIN was not included in the recall. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 106,000.

NHTSA ODI #11631816

111,000 miles · Nov 26, 2024
EngineEngine And Engine Cooling

The contact owns a 2018 Kia Optima. The contact stated that while his wife was driving at an undisclosed speed, the vehicle went into LIMP Mode, and the check engine warning light was illuminated. The vehicle was restarted; however, the failure recurred while driving. The vehicle was taken to the dealer, where it was diagnosed a…

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The contact owns a 2018 Kia Optima. The contact stated that while his wife was driving at an undisclosed speed, the vehicle went into LIMP Mode, and the check engine warning light was illuminated. The vehicle was restarted; however, the failure recurred while driving. The vehicle was taken to the dealer, where it was diagnosed and determined that the spark plugs had failed and needed to be replaced. The vehicle was repaired; however, the failure recurred while driving. The vehicle was towed to the dealer, where it was diagnosed that the engine had failed and needed to be replaced. The contact was informed by the dealer that the repair could not be covered due to the poor maintenance of the vehicle; however, upon providing all the maintenance records, the dealer informed the contact that the vehicle could not be repaired unless the engine had fully seized. The dealer offered a trade-in offer; however, the contact declined the offer. The vehicle was not repaired. The manufacturer was made aware of the failure. The approximate failure mileage was 111,000.

NHTSA ODI #11627569

Mileage unknown · Sep 26, 2024
Engine And Engine Cooling

The contact owns a 2018 Kia Optima. The contact stated that the vehicle was consuming an excessive amount of engine oil. The engine and oil warning lights were flashing on the instrument panel. The vehicle was taken to the local dealer, who performed an oil consumption test. The vehicle failed the oil consumption test and determ…

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The contact owns a 2018 Kia Optima. The contact stated that the vehicle was consuming an excessive amount of engine oil. The engine and oil warning lights were flashing on the instrument panel. The vehicle was taken to the local dealer, who performed an oil consumption test. The vehicle failed the oil consumption test and determined that the vehicle was consuming an excessive amount of engine oil. The vehicle was not repaired. The vehicle was taken to another local dealer, Monroeville Kia (3721 William Penn Hwy, Monroeville, PA 15146); who informed the contact there was no recall coverage on the VIN for the failure. The vehicle was not diagnosed or repaired. The manufacturer was not contacted. The failure mileage was unknown.

NHTSA ODI #11616664

60,000 miles · May 23, 2024
Engine And Engine Cooling

The contact owns a 2018 Kia Optima. The contact stated that after starting the vehicle, there was an abnormal amount of smoke coming from the exhaust pipe. The contact inspected the dipstick and discovered that the engine oil level was low. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufa…

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The contact owns a 2018 Kia Optima. The contact stated that after starting the vehicle, there was an abnormal amount of smoke coming from the exhaust pipe. The contact inspected the dipstick and discovered that the engine oil level was low. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 60,000.

NHTSA ODI #11590383

98,000 miles · May 22, 2024
Engine And Engine Cooling

The contact’s sister owns a 2018 Kia Optima. The contact stated that the vehicle was consuming an excessive amount of engine oil. The contact stated that engine oil needed to be added every 2-3 weeks. The contact stated that an unknown warning light was illuminated. The vehicle received an unknown repair; however, the failure pe…

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The contact’s sister owns a 2018 Kia Optima. The contact stated that the vehicle was consuming an excessive amount of engine oil. The contact stated that engine oil needed to be added every 2-3 weeks. The contact stated that an unknown warning light was illuminated. The vehicle received an unknown repair; however, the failure persisted. The vehicle was taken to the dealer and was diagnosed with valve cover gasket failure. The valve cover gasket was replaced however, the failure persisted. The failure persisted and the vehicle was taken to an independent mechanic where it was discovered that there was an oil leak as well as there was excessive oil consumption. The independent mechanic stated that the engine might need to be replaced; however, a diagnostic result was not confirmed. The vehicle had not been repaired. The manufacturer was not made aware of the failure. The failure mileage was 98,000.

NHTSA ODI #11590203

Official recalls

2

23V594000 · 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

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.