Home · 2015 Kia Optima Phev · Complaints

What 1,000 owners told NHTSA about the 2015 Kia Optima Phev

These are the actual owner complaints behind this car’s reliability verdict, filed with the federal government, unedited. They’re unverified reports, not confirmed defects: read them as leads for your pre-purchase inspection, not a diagnosis.

All (1,000)Crash / fire / injury (103)Engine (617)Electrical system (134)Brakes (89)Body & structure (76)Steering (68)Fuel system (54)Transmission & drivetrain (49)Speed control (35)Engine & cooling (29)Airbags (26)

29 of 1,000 complaints match · Engine & cooling · clear filters · page 1 of 2

Jul 14, 2026Engine & coolingFire

The contact owned a 2015 Kia Optima. The contact stated that while driving to the residence, the vehicle caught on fire. The contact stated that while at a traffic light, the vehicle suddenly shut off. After exiting the vehicle, the hood was opened, and there was smoke coming from the engine compartment. The contact called an independent mechanic and, within two minutes, became aware of the fire. The contact called 911 for the Emergency Services. The Fire Department arrived and extinguished the fire. There was no injury sustained. There were no warning lights illuminated. The vehicle was previously taken to an unknown local dealer, where it was diagnosed that the engine was leaking with a blown head gasket. The engine was replaced. The vehicle was towed from the scene and was deemed a total loss by the insurance company. The manufacturer was contacted and opened a case. The failure mileage was approximately 212,000.

NHTSA ODI 11750336

May 29, 2026Engine & coolingEngineFire

The contact owns a 2015 Kia Optima. The contact stated that while accelerating at 55 MPH, there was an abnormal burning smell detected. While driving, she was alerted by another driver who informed her that the vehicle was on fire. The passengers were able to exit the vehicle safely. The vehicle was engulfed in flames. There were no reported injuries. The vehicle was towed to a tow lot. The vehicle was previously taken to an independent mechanic, who said the engine was bad. The engine was previously replaced at 147,000 miles. The fire department was able to extinguish the fire. A police report was filed. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was contacted, but no assistance was provided. The failure mileage was approximately 60,000.

NHTSA ODI 11740785

Mar 3, 2026Engine & cooling

The contact owns a 2015 Kia Optima. The contact stated that while driving at 40 MPH, there was smoke coming from underneath the hood, and the engine overheated. The check engine warning light was illuminated. The contact was able to pull over to the side of the road and add coolant to the coolant reservoir. The vehicle slowly started and was driven to the destination. The contact stated that the engine was overheating if driven for more than 10 minutes. The vehicle was taken to an independent mechanic, where it was determined that the vehicle was experiencing excessive coolant consumption, and coolant was added as needed. The mechanic determined that the failure might be related to the engine. The vehicle failed to start and was undrivable. The vehicle was not repaired. The dealer was contacted and referred the contact to the manufacturer for assistance. The manufacturer was contacted, and a case was filed. The failure mileage was approximately 124,000.

NHTSA ODI 11721647

Sep 26, 2025Engine & coolingFire

The contact owns a 2015 Kia Optima. The contact stated that while his son was driving at 60 MPH, the instrument panel was entirely illuminated, and he pulled over. There was smoke inside the cabin. The occupants were able to exit the vehicle. An independent mechanic opened the hood and noticed a fire. They were able to extinguish the fire. The vehicle was towed to the local dealer, where it was diagnosed that the drive belt had failed and had broken. There was friction from the drive belt, which caused the fire. The vehicle was not repaired. The manufacturer was contacted, who opened a claim. The manufacturer had called the contact, but no further assistance was provided. The approximate failure mileage was 114,000.

NHTSA ODI 11689846

Jun 11, 2025Engine & cooling

See attached document for complaint.

NHTSA ODI 11666376

Jun 4, 2025Engine & cooling

The contact owns a 2015 Kia Optima. The contact stated while driving approximately 75 MPH, the vehicle independently decelerated to approximately 60 MPH. The contact stated that the check engine warning light was flashing. The vehicle was towed to the local dealer, but the cause of the failure was not yet determined. The contact stated that a knock sensor was installed to monitor the engine performance. The manufacturer was not yet contacted regarding the failure. The failure mileage was 70,000. The VIN was not available.

NHTSA ODI 11664783

May 20, 2025Engine & cooling

The contact owns a 2015 Kia Optima. The contact stated while driving approximately 65 MPH, the check engine warning light illuminated. The contact stated that the vehicle started to lose motive power. The contact pulled off the roadway and heard an abnormal grinding sound coming from underneath the vehicle. The contact turned off the vehicle and the vehicle was unable to be restarted. The contact had the vehicle towed to a local dealer who diagnosed the vehicle and determined that the engine needed to be replaced. The contact was advised that the following DTC were retrieved: P0076; P0079; B2519; B2521. The vehicle was not repaired. The manufacturer was informed of the failure and informed the contact that there was no recall on the VIN for the engine. The failure mileage was approximately 140,000.

NHTSA ODI 11662070

Apr 9, 2025BrakesEngine & cooling

See attached document for complaint.

NHTSA ODI 11653673

Dec 23, 2024Engine & cooling

The contact owns a 2015 Kia Optima. The contact stated that while driving at various speeds, the engine stalled. The engine would decrease in engine RPMs. The vehicle was able to restart however the failure recurred. The vehicle was towed to the residence, and then to a dealer. The vehicle was diagnosed and the contact was provided manufacturer's recall number: PI1802A. The manufacturer was contacted and informed the caller the ECU Logic Upgrade should have been completed first before the engine could be repaired. The failure was recurring and the contact parked the vehicle to be not driven no longer as it was a safety concern. The failure mileage was 84,850.

NHTSA ODI 11632148

Aug 20, 2024Engine & coolingElectrical system

The contact owns a 2015 Kia Optima. The contact stated while driving at an undisclosed speed, the accelerator pedal was depressed; however, the vehicle failed to accelerate as intended. Additionally, the check engine warning light illuminated, and the vehicle turned off unintendedly. The vehicle was towed to the dealer where it was diagnosed with engine failure. The contact was informed that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure; however, the contact was informed that the repair was not covered under the Technical Service Bulletin NHTSA ID: 10252085 (Electrical System, Engine and Engine Cooling); with a similar failure description. The failure mileage was approximately 92,394.

NHTSA ODI 11609618

Jun 11, 2024Engine & coolingEngine

The contact owns a 2015 Kia Optima. The contact stated while driving approximately 40 MPH and depressing the accelerator pedal to merge onto the highway, the vehicle failed to respond as needed. The contact stated that she had not observed any warning lights being illuminated. The contact pulled off the highway and had the vehicle towed to a local mechanic. The mechanic diagnosed the vehicle and determined that the engine had no oil and had seized. The mechanic determined that the engine needed to be replaced. The vehicle was repaired. The manufacturer was not informed of the failure. The failure mileage was approximately 84,000.

NHTSA ODI 11593662

May 16, 2024Engine & coolingCrash

The contact owns a 2015 Kia Optima. The contact stated while the daughter was driving at approximately 80 MPH and attempting to pass a tractor-trailer in the left lane, the vehicle behind her aggressively merged into the same lane causing a crash to the passenger side of the vehicle. The other vehicle fled the scene. The contact's daughter merged to the shoulder of the road. There was damage to the front passenger side door, and front passenger wheel well, and tire. The vehicle failed to restart. The police were on the scene however no Police Report was filed. There were no injuries reported. The vehicle was towed to a collision center for cosmetic repairs but the vehicle failed to start. The vehicle was then towed to a local dealer. The dealer diagnosed that the engine had failed and needed to be replaced. The dealer mentioned a recall related to the engine, but it was not eligible for engine replacement because the vehicle had not had a software update performed for the engine. The vehicle was not repaired. The contact had researched online and related the failure to NHTSA Campaign Number: 17V224000 (Engine and Engine Cooling). The manufacturer was notified of the failure. The failure mileage was approximately 73,000.

NHTSA ODI 11589024

Apr 24, 2024Engine & coolingEngine

The contact owns a 2015 Kia Optima. The contact stated that while driving 30 MPH, there was an abnormal smoke odor inside the interior of the vehicle. No warning lights were illuminated. The vehicle was taken to an independent mechanic, who determined that there was an oil leak in the engine compartment. The vehicle was not repaired. The vehicle was then taken to the dealer, who diagnosed a failure with the engine, determining that the engine was consuming oil abnormally quick, and the engine might soon need to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure but provided no assistance. The failure mileage was unknown.

NHTSA ODI 11584987

Apr 2, 2024BrakesEngine & cooling

The contact owns a 2015 Kia Optima. The contact received notification of NHTSA Campaign Number: 23V652000 (Service Brakes, Hydraulic) however, the part to do the recall repair was not yet available. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The contact stated that when starting the vehicle, the check engine and several other warning lights illuminated. The contact stated that the vehicle was overheating, and the contact was concerned about a possible fire. The contact had driven the vehicle to an independent mechanic who was unable to duplicate the failure. Additionally, the contact stated that while driving at approximately 60 MPH, the vehicle independently accelerated. The contact stated that several unknown warning lights were illuminated. The contact pulled over and stopped the vehicle. The contact stated that she waited about 30 minutes and restarted the vehicle and drove back to her residence. The manufacturer was not made aware. The failure mileage was approximately 151,000. VIN tool confirms parts not available.

NHTSA ODI 11580595

Dec 22, 2023Engine & cooling

The contact owns a 2015 Kia Optima. The contact stated while driving 20 MPH, the vehicle inadvertently lost motive power. The contact pulled over to the shoulder of the roadway, where the vehicle failed to restart. The check engine and low engine oil warning lights were illuminated. The vehicle was towed to an independent mechanic, who determined that an unknown fluid had leak and damaged the electrical components in the engine compartment, causing the engine to seize. The vehicle was not repaired. The manufacturer was notified of the failure but referred the contact to the NHTSA hotline for assistance. The approximate failure mileage was 81,000.

NHTSA ODI 11561537

Dec 6, 2023Engine & coolingEngine

The contact owns a 2015 Kia Optima. The contact stated that while driving at approximately 40 MPH, the engine seized. After restarting the vehicle, the vehicle shut off. The vehicle was towed to the local dealer, where it was diagnosed that the engine had seized and needed to be replaced. The contact was informed that there was metal in the intake and exhaust cam shaft. There were metal shavings in the oil. The contact was also informed that the pistons were off by twenty-four degrees. There was an indication that cylinders #1, #2, and #4 had misfired. The vehicle was not repaired. The manufacturer was contacted, but no assistance was provided. The failure mileage was approximately 102,589.

NHTSA ODI 11558789

Jun 13, 2023Engine & coolingFire

The contact owns a 2015 Kia Optima. The contact's daughter was driving at approximately 60 MPH when numerous lights on the dashboard illuminated. The contact stated that her daughter said that the vehicle stalled, however, she was in the right-hand lane and pulled over. The daughter said that smoke was being emitted from the engine compartment. The contact stated her daughter was picked up by family and the vehicle was left at the side of the highway. The contact stated that the daughter's companion retrieved the vehicle. The contact stated that he opened the hood and checked the oil and observed that there was no oil showing on the dipstick. The contact filled the vehicle's oil reservoir and started the vehicle. The contact said that he also reported that all panel warnings illuminated and the vehicle had begun to emit smoke. The contact stated he pulled off the roadway, opened the hood, and observed smoke and flames being emitted from under the engine block. The contact stated he had immediately closed the hood and moved away from the vehicle. The contact stated that he reported that the vehicle continued to emit smoke but no more flames were observed. The contact had the vehicle towed to a local dealer, where it was diagnosed and determined that the engine had seized and needed to be replaced. The vehicle had not been repaired. The manufacturer had been informed of the failure. The failure mileage was approximately 184,000.

NHTSA ODI 11526832

Apr 3, 2023Engine & cooling

The contact owns a 2015 Kia Optima. The contact stated while driving approximately 40 MPH, the contact stated he heard an abnormal knocking sound coming from the engine compartment. The contact observed white smoke coming from under the hood. The contact was able to pull over with the engine still running however, when he stopped and turned off the vehicle, he was unable to restart the vehicle. The contact stated that the oil and battery warning lights were illuminated. The contact had the vehicle towed to an independent mechanic where it was diagnosed and determined that the engine needed to be replaced. The vehicle had not been repaired. The manufacturer had not been informed of the failure. The contact researched online and related the failure to NHTSA Campaign Number: 17V224000 (Engine and Engine Cooling). The failure mileage was approximately 83,000.

NHTSA ODI 11515219

Feb 8, 2023Engine & cooling

The contact owns a 2015 Kia Optima. The contact stated while his wife was driving at approximately 35 MPH, the vehicle stalled. The contact stated that his wife steered the vehicle to the side of the road and parked the vehicle. The contact stated no warning light was illuminated. The contact had the vehicle towed to an independent mechanic where it was diagnosed and determined that the engine needed to be replaced due to a lack of engine oil. The contact stated that he had never noticed a leak and had followed the maintenance schedule for oil changes. The vehicle had not been repaired. The manufacturer had been informed of the failure. The contact researched online and related the failure to NHTSA Campaign: 17V224000 (Engine and Engine Cooling). The failure mileage was approximately 117,000.

NHTSA ODI 11506237

Feb 3, 2023Engine & cooling

The contact owns a 2015 Kia Optima. The contact stated that while operating the vehicle, there was a knocking sound coming from the engine compartment. After stopping at a red light, the engine suddenly failed. The vehicle was towed to the local dealer who diagnosed that the engine was faulty and needed to be replaced. The vehicle was not yet repaired. The manufacturer was notified of the failure, but no assistance was offered. The failure mileage was 88,000.

NHTSA ODI 11505324

Dec 20, 2022AirbagsEngine & cooling

The contact owns a 2015 Kia Optima. The contact stated while driving approximately 45 MPH, the air bag warning light was illuminated. The contact stated while driving at various speeds, the vehicle was jerking. The contact stated that while depressing the brake pedal, the vehicle failed to respond. The traction control, air bag, power steering assist, ABS, and check engine warning lights were illuminated. The vehicle was taken to an independent mechanic twice, and the front passenger’s side wheel speed sensor and the ECU were replaced twice; however, the failure persisted. The mechanic advised the contact to take the vehicle to the local dealer. The vehicle was taken to Clay Cooley Kia (1247 E Airport Fwy, Irving, TX 75062) where it was diagnosed that the ECU needed to be replaced. The vehicle was repaired; however, the failure recurred, and various unknown warning lights were illuminated. The vehicle was then taken to Vanguard Kia of Arlington (1501 E Interstate 20, Arlington, TX 76018) where it was diagnosed that the ECU, front passenger’s side wheel speed sensor and air bag clockspring needed to be replaced. The vehicle remained at the dealer awaiting the repair. The manufacturer was made aware of the failure. The approximate failure mileage was 200,000.

NHTSA ODI 11498242

Dec 14, 2022EngineEngine & cooling

My vehicle engine blew while driving on the highway going about 65 no warning or signs other then the amount of oil that it was consuming. I am just now hearing about the class action lawsuits for my specific engine the Theta 2.0 which I have already verified it is part of it. KIA is saying it's the wrong part of the engine that is blown that it want be qualify for the engine replacement. I have kept my oil changed regularly and just recently noticed it started to consume godly amounts of oil no leak, or smell it was literally disappearing it is not normal to add almost 4qts of oil every 2 weeks or so. These engines need to be recalled not placed on a "service bulletin" and they pick and choose which to fix. Point is they are ticking time bombs and something need to be done they will not back their products and us consumers are left to suffer.

NHTSA ODI 11497491

Nov 15, 2022Engine & coolingSpeed control

The contact owns a 2015 Kia Optima. The contact stated that while driving at an undetermined speed, the vehicle failed to accelerate and stalled. There were no warning lights illuminated. The vehicle was towed to the local dealer where it was diagnosed that an engine replacement was needed. The vehicle was not repaired. The manufacturer was notified and informed him that he had failed to complete the knock sensor detection system (KSDS) repair and provided no additional assistance. The failure mileage was approximately 106,000.

NHTSA ODI 11493608

Sep 1, 2022Engine & cooling

The contact owns a 2015 Kia Optima. The contact stated while her mother was driving approximately 45-50 MPH, the vehicle lost motive power and stalled. There were no warning lights illuminated. The contact's mother depressed the brake pedal and veered to the side of the road. The vehicle failed to restart after several attempts and emitted abnormal loud knocking sounds. The vehicle was towed to the contact's residence. The vehicle was then towed the dealer where it was diagnosed that the engine needed to be replaced; however, the contact stated that an oil change was completed on the vehicle approximately one month earlier. The manufacturer was not notified of the failure. The failure mileage was unknown.

NHTSA ODI 11482491

Aug 18, 2022Engine & coolingEngine

The contact owns a 2015 Kia Optima. The contact stated that while driving 20 MPH, an abnormal knocking noise was coming from the engine. The vehicle then lost motive power and stalled with the check engine warning light illuminated. The contact had the vehicle towed to an independent mechanic who diagnosed the vehicle with engine failure. The vehicle was then towed to a dealer where she was given an estimate for the repair. The manufacturer was notified of the failure and the contact was informed that the vehicle would not be covered under warranty or recall. The vehicle was not repaired. The failure mileage was approximately 99,000.

NHTSA ODI 11480002

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Working with the data? Download all 1,000 complaints as CSV · fetched from NHTSA July 19, 2026

How to use these: a complaint is one owner’s report, filed voluntarily and published unverified. Patterns matter more than any single story. If several owners describe the same failure at similar mileage, put that system at the top of your pre-purchase inspection list. Back to the full 2015 Kia Optima Phev verdict →