Problems · by component

2015 Kia Optima engine problems

624 owner complaints to NHTSA about the 2015 Kia Optima cite engine, 62% of all 1,011 complaints for this model year.

Complaints
624
62% of all complaints
Crashes
9
Reported by owners
Fires
48
Reported by owners
Injuries
9
Reported by owners
01 —Owner reports

What owners say about the engine

Verbatim from NHTSA complaints, newest first
“I was driving to work when all of the sudden I was pressing my gas, but I wasn't accelerating. I noticed my brakes and steering wheel were hard to push and turn. My car stopped in the middle of the road. I turned off my car and tried to turn the ignition and all I got was a single click. My engine, battery and oil lights were now on. They were not before. After 25 minutes in the middle of the road a sheriff came and pushed me to the side. When I put my car in neutral it was hard to steer and my brakes were hard to push. I was terrified that I was not going to be able to stop. I was scared I was going to be hit and someone would get seriously injured. I then received a call from Cascade Automotive saying that my engine seized from rod bearing failure but my engine was under warranty under the Kia Engine Class Settlement. I called Kia Consumer service and they said my Vin# qualified and was under warranty. I then had it towed to Kia of Puyallup. They confirmed it was a Rod Bearing failure that caused the seizure and told me it did qualify for the warranty. But then told me since I didn't get the HECU fuse update its void. I told them I never got a notice for the…”
Owner complaint to NHTSAFiled Nov 4, 2026EngineODI 11775778
“There is a known issue with this vehicle and the fix by KIA is not safe nor fair to the consumer. Kia's knock sensor recall centers on the Knock Sensor Detection System (KSDS) software update for Theta II GDI engines. The update listens for rod bearing wear, triggers a check engine light and limp mode via Code P1326, and extends the engine warranty up to a lifetime or 15 years/150,000 miles. My problem is that we had to car in on May of 2026 after in went into limp mode. They updated the software. The car again went into limp mode on 10/21/2026, they updated the software again. My focus here is the fact that it is a known issue and they say it still does not meet the parameters for an engine replacement. It is a severe issue that is dangerous and inconvenient to the driver. You are afraid to take it on a trip or even take it on a highway. My 20 year old daughter drives this to college. Can you imagine a car going into limp mode on a majory US highway? Limp mode essentially does not allow a vehicle to go above 2K RPM. You cant go up a hill over 35 and on a highway, on a flat road you "might" be able to go 55 MPH. My daughter goes to college 4 hours away. This…”
Owner complaint to NHTSAFiled Oct 23, 2026EngineODI 11773169
“My 2015 KIA optima experienced a catastrophic engine fire while I was driving. There was no warning, I just heard a boom in the engine bay the breaks stopped working and all electrical cut out. As I'm coasting, because I'm unable to stop, flames started to come in through under the dash. I couldn't turn the car off, nor put it in park so the doors stayed locked. The driver window was opened just enough for me to grab the top and break it, allowing me to crawl out. The car coasted itself to the shoulder then blew up (I had a full tank of gas.). All this happened in the manner of 30 to 35 seconds. It's important to note that KIA just replaced the engine 2 months prior to this incident.”
Owner complaint to NHTSAFiled Aug 24, 2026Unknown or other, Engine, Fuel/propulsion systemFire reportedODI 11759158
“The engine in my vehicle failed while putting the car into reverse to back into my garage. I thank God I wasn't on the road when this happened. I took the car into a mechanic who confirmed that the engine was locked and that the car was very low on oil(even though I had my oil changed by him a few months prior). There was an undetected oil leak that led to the engine failure. The warning indicators didn't appear on my dash until after my engine failed.”
Owner complaint to NHTSAFiled Aug 19, 2026EngineODI 11758113
“This is a formal vehicle safety complaint regarding a manufacturer's active refusal to remedy a known safety defect under an active recall campaign guidelines.My 2015 Kia Optima Turbo experienced an active internal mechanical engine knock, violent sputtering, and a complete engine seizure. The vehicle is currently sitting un-driveable at an authorized Kia dealership.The required Knock Sensor Detection System (KSDS) software update was successfully completed on this vehicle prior to the incident, legally qualifying it for a 100% free long-block engine replacement under the manufacturer's active Lifetime Warranty extension. However, the dealership service department is actively withholding the safety warranty paperwork and refusing to submit the diagnostic photos and engine seizure data to corporate for warranty approval unless I agree to pay an additional $800 out of pocket for an external throttle body and O2 sensor.I have explicitly declined the retail accessory charges five separate times. I only authorize the replacement of my front sway bar links. Instead of separating the ticket and processing the free engine block safety remedy, the dealer is holding my…”
Owner complaint to NHTSAFiled Aug 13, 2026Steering, Engine, Fuel/propulsion systemODI 11756632
“My girlfriend was driving on interstate 95 to pick me up from the metro. The engine suddenly cut off in a manner that appears to have melted the wiring harness of the vehicle, risking fire. She was able to safely get to the side of the road and call a tow. After taking it to a local repair shop, they diagnosed the issue as related to the KSDS recall. We had it towed to the dealership that has also confirmed it is related to the recall. The engine is completely seized following this incident and it's worth noting that Kia is completely denying the engine repair claim as the KSDS update was not installed prior.”
Owner complaint to NHTSAFiled Jul 20, 2026EngineODI 11751632

Showing 6 of 624 reports. Read every report on NHTSA.gov.

Data from NHTSA Complaints API (owner reports, unverified) · synced Nov 10, 2026NHTSA vehicle page

Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.