Check a VIN

2015 Kia Optima engine problems

649 complaints (64% of all complaints for this car). Typical mileage when it fails: 88,000. 11 crashes reported.

owner complaints
649
of this car's complaints
64%
typical mileage
88,000
crashes
11
recalls
1

Which part fails

  • Exhaust system: manifold/header/muffler/tail pipe
    1
  • Engine: oil/lubrication
    1
  • Engine: engine control module (ecu/ECM)
    1

At what mileage

Complaints by mileage at the time of the problem.

0k-25k
25k-50k
50k-75k
75k-100k
100k-125k
125k-150k
150k-175k
175k-200k
200k+

Kia Optima engine problems in other years

20012005201020152020

Specific symptoms reported on the 2015 Kia Optima engine

Phrases found in the owners' own descriptions, so one complaint can mention several symptoms.

Engine failure 244Knocking 149Check engine light 140Stalling 140Loss of power 59Won't start 42Oil consumption 39Overheating 8

Related recalls

EngineReported December 19, 2018 · 71,653 vehicles affected
What is wrong
Kia Motors America (Kia) is recalling certain 2011-2017 Optima, 2012-2017 Sorento and 2011-2018 Sportage vehicles that previously received an engine replacement under recall number 17V‑224, warranty, or the Knock Sensor Detection System (KSDS) Product Improvement Campaign. The high pressure fuel pipe that connects to the fuel pump outlet may have been damaged, misaligned or improperly torqued during the engine replacement procedure, possibly causing a fuel leak.
Risk
A fuel leak in the presence of an ignition source can increase the risk of a fire.
Remedy
Kia has notified owners, and dealers will inspect and replace the fuel pipe, as necessary, free of charge. The recall began January 17, 2019. Owners may contact Kia customer service at 1‑800‑333‑4542. Kia's number for this recall is SC172.

Recall number 18V907000 · Recall details

Related investigations

Loss of Motive PowerOpened September 12, 2022, closed December 12, 2023

the federal safety agency 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 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 the federal safety agency 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 the federal safety agency's possession, and the potential risks to motor vehicle safety implicated by the petitioners' allegations, the federal safety agency does not believe that a formal investigation is warranted. Therefore, the petition is denied. A Federal Register Notice (FRN) further detailing the federal safety agency’s reasons for denial of the petition will be published. The reference numbers for the complaints to the federal safety agency 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

DP22003

What 2015 Kia Optima owners say

Most recent owner complaints, unedited.

Filed Nov 4, 2026 · Engine · WA

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 recall. They said it didn't matter and said to fix it, it would be $6700. I called Kia Consumer again and asked what can be done and they said nothing. I asked if they had any record of sending me or my dad ([XXX]) the recall notice and they said no and he wasn't in their records as the registered owner. I then asked since they have no record of sending the recall notice to me or my dad and I had no way of knowing about the HECU fuse if the warranty is good now and they said no, I should have looked for recall. There were no warning signs. I have maintained my car and had the oil changed regularly. My safety was put in jeopardy because Kia failed to notify me of a faulty engine and the HECU fuse. I asked for the records saying no notice was given and they said it was against their policy to send that. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORM

Filed Oct 23, 2026 · Engine · NC

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 creates a very unsafe, dangerous and inconvenient environment. KIA is hoping that they can buy time until these vehicles fail for some other reason and they dont have to pay the cost for a new engine.... ALL at the consumers peril. To put this in perspective, if you have a vehicle with a "low tire pressure" warning, does lowering the sensors parameters fix the problem.... No, it just turns off the warning and you are driving a car with low tire pressure.

Filed Sep 20, 2026 · Acceleration, Engine · KY

My energy in my car started messing up with only 150,000 miles it had a long knocking sound and it would not got over 20 miles while driving

Filed Aug 24, 2026 · Engine, Fuel system · AZ · fire

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.

Filed Aug 20, 2026 · Engine · 123,000 miles · TX

The contact owns a 2015 Kia Optima. The contact stated that for over 8 years, the vehicle was experiencing excessive oil consumption. There was no warning light illuminated. The contact became aware that there was an oil leak on the ground underneath the vehicle. The vehicle was taken to the dealer on several occasions for the oil consumption failure; however, the dealer was unable to find a fault with the vehicle. The dealer had not yet provided a cause for the oil leak. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was 123,000.

Filed Aug 19, 2026 · Engine · GA

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.

Filed Aug 13, 2026 · Engine, Fuel system · MA

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 safety warranty hostage to force a retail sale. Furthermore, a manufacturer consumer care representative recently refused to listen to my request on this matter and dropped the call.The manufacturer is using internal technical advice to block a court-ordered safety remedy and is allowing a dealership to use unauthorized retail accessory charges to deny me a safe, operating vehicle. I request immediate federal intervention to force the manufacturer to release the free engine block safety replacement order to the dealer and halt these predatory dealer practices.

Filed Jul 23, 2026 · Engine · 140,000 miles · CT · fire

The contact owns a 2015 Kia Optima. The contact stated that while driving at an undisclosed speed, the vehicle stalled. During the failure, several unknown warning lights flashed on the instrument panel and there was smoke coming from under the hood of the vehicle. The contact exited the vehicle, and there were flames coming from underneath the hood. The Fire Department was called to the scene and extinguished the flames. During the failure, the vehicle was destroyed. A Police report was filed, and the vehicle was towed to a tow lot. The cause of the failure was not yet determined. The manufacturer was notified of the failure. The contact stated that the original engine was previously replaced by the local dealer due to a previous recall. No further information was available. The failure mileage was 140,000.

Filed Jul 20, 2026 · Engine · VA

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.

Filed Jul 14, 2026 · Engine · 212,000 miles · MD · fire

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.

Questions about the 2015 Kia Optima engine

Does the 2015 Kia Optima have engine problems?

Owners have filed 649 complaints about the engine of the 2015 Kia Optima, 64% of all its complaints, more than any other problem.

At what mileage do 2015 Kia Optima engine problems start?

The typical (median) mileage in owner complaints is 88,000 miles.

Is there a recall for the 2015 Kia Optima engine?

Yes, 1 recall: 18V907000. Check your VIN to see if your car still needs the free repair.

Other 2015 Kia Optima problems

Electrical 135Brakes 90Body 76Steering 69Fuel system 56Transmission 49Acceleration 36Airbags 26Lights 23Driver assistance 22Visibility 9Suspension 6Wheels 5Tires 3Seat belts 2Seats 2

VIN decoder

See the problems and recalls for an exact car

Buying a used 2015 Kia Optima?

Check the exact car before you pay: accidents, salvage or flood titles, odometer readings and previous owners.

Check its history