2015 Kia Optima
Problems, recalls and owner-reported issues
Engine is the leading concern among 1,008 owner complaints filed for this model year. This is the 2nd highest complaint count among 20 Optima model years with reports.
Of the 2015 reports, 31 involved a crash and 74 involved a fire. 23 people were injured and 1 person died.
What owners report most often
Recalls and investigations
Service brakes, hydraulic, antilock/traction control/electronic limited slip, control unit/modulePark outsideSep 25, 2023
Kia America, Inc. (Kia) is recalling certain 2010-2019 Borrego, 2014-2016 Cadenza, 2010-2013 Forte, Forte Koup, Sportage, 2015-2018 K900, 2011-2015 Optima, 2011-2013 Optima Hybrid, Soul, 2012-2017 Rio, 2011-2014 Sorento, and 2010-2011 Rondo vehicles. The Hydraulic Electronic Control Unit (HECU) may experience an electrical short, which can result in an engine compartment fire while parked or driving.
An engine compartment fire while parked or driving can increase the risk of injury.
Owners are advised to park outside and away from structures until the recall repair is complete. Dealers will replace the HECU fuse, free of charge. Interim notification letters, notifying owners of the safety risk, were mailed November 14, 2023. Owner notification letters were mailed March 29, 2024 through June 18, 2024. Owners may contact Kia customer service at 1-800-333-4542. Kia's number for this recall is SC284.
Campaign 23V652000 on NHTSA.gov
Service brakes, hydraulic, antilock/traction control/electronic limited slip, control unit/modulePark outsideMay 10, 2021
Kia Motors America (Kia) is recalling certain 2013-2015 Optima and 2014-2015 Sorento vehicles previously recalled under recall 20V-519. Brake fluid may leak inside the Hydraulic Electronic Control Unit (HECU), possibly resulting in an electrical short.
An electrical short in the HECU increases the risk of a fire while parked or driving.
Owners are advised to park outside and away from other vehicles and structures until the recall repair is completed. Dealers will install a new multi-fuse, and inspect the HECU for leaks, replacing the HECU if necessary, free of charge. Owner notification letters were mailed on July 2, 2021. This recall supersedes previous NHTSA recall number 20V-519. Owners may contact Kia customer service at 1-800-333-4542. Kia's number for this recall is SC212.
Campaign 21V331000 on NHTSA.gov
Service brakes, hydraulic, antilock/traction control/electronic limited slip, control unit/modulePark outsideAug 27, 2020
Kia Motors America (Kia) is recalling certain 2013-2015 Optima and 2014-2015 Sorento vehicles. Brake fluid may leak inside the Hydraulic Electronic Control Unit (HECU), possibly resulting in an electrical short.
If the HECU short circuits, there is an increased risk of an engine compartment fire.
Kia will notify owners, and dealers will inspect the HECU for leaking brake fluid and replace the HECU if necessary, free of charge. Owners are advised to park outside and away from other vehicles and structures until the recall repair is completed. The recall began October 20, 2020. Owners may contact Kia customer service at 1-800-333-4542. Kia's number for this recall is SC197.
Campaign 20V519000 on NHTSA.gov
Fuel system, gasoline, delivery, hoses, lines/piping, and fittingsDec 19, 2018
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.
A fuel leak in the presence of an ignition source can increase the risk of a fire.
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.
Campaign 18V907000 on NHTSA.gov
Representative owner complaints: engine
647 reports, newest first. Show all
Engine, Jan 29, 2026
The contact owns a 2015 Kia Optima. The contact stated that while driving at an undisclosed speed, the engine seized, and the vehicle stalled. The vehicle was able to coast to the side of the road. The check engine warning light and several other warning lights were illuminated. The contact raised the hood, and there was a burning odor coming from the engine. The vehicle was towed to the place of employment. A mobile mechanic arrived at the place of employment and used a handheld code reader to diagnose the vehicle, but no DTC was retrieved, and no cause for the failure was determined. The starter was replaced; however, the vehicle failed to restart. The vehicle was towed to an independent mechanic, who diagnosed that the engine had failed and needed to be replaced. The vehicle was not repaired due to the cost. The contact stated that the vehicle was purchased six months prior to the failure. The manufacturer was not made aware of the failure. The failure mileage was approximately 96,000.
Engine, Jan 25, 2026
I've had car for not very long and rid bearings now all of a sudden went out and engine is bad at this point and don't understand why my vehicle wouldn't be included in all the different recalls for 2015 optima because it's one of the years of theta 2 engine being recalled and mine says 0 recalls why is that?
Steering, Engine, Jan 7, 2026
Engine seized
Engine, Dec 18, 2025, fire
The contact owned a 2015 Kia Optima. The contact stated that while driving at 55 MPH, while depressing the accelerator pedal, the contact could smell a burning smell within the vehicle, and then he noticed smoke coming from the front of the vehicle. No warning lights illuminated. The contact pulled over to the right side of the road and exited the vehicle, opened the hood, and noticed smoke and flames coming from the engine. The contact exited the vehicle and stood on the side of the road, and called 911. No injuries were sustained. No medical attention was required. The contact mentioned the police showed up on the scene; however, he could not remember if he received a police report. A fire department report was filed. The fire department extinguished the fire. The vehicle was destroyed. The vehicle was towed to Pro-Cars. The vehicle was not repaired. The contact mentioned he contacted his insurance company, and they informed him that the vehicle was a total loss. The manufacturer was notified of the failure, and they transferred him to the escalation department and informed him that an inspector would inspect the vehicle, and he had to wait seven to ten business days for a resolution. The failure mileage was 53,000.
Engine, Dec 16, 2025
The engine in my 2015 Kia Optima suddenly seized due to connecting rod bearing failure at approximately 55,000 miles. This vehicle is known to be affected by the Theta II engine defect. I was never aware of the seriousness of the recall software update and did not receive meaningful notice that failure to install it could result in catastrophic engine failure. Kia has denied engine warranty coverage solely because the software update was not installed prior to failure, despite the defect existing regardless of software.
Engine, Dec 15, 2025
My 2015 Kia Optima (VIN [XXX] ) experienced sudden engine failure and stalled while driving at approximately 90,000 miles. There was no oil pressure warning light and no knocking prior to failure. The check engine light illuminated shortly before the stall. Kia is denying engine coverage solely because an ECU/KSDS update was not performed. I was never notified of this update because Kia had an incorrect address on file for me. This failure is consistent with known Theta II connecting rod bearing defects that have resulted in recalls and warranty extensions. I believe this is a safety-related defect and am requesting review. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
Engine, Dec 10, 2025
The contact owns a 2015 Kia Optima. The contact stated that while driving at an undisclosed speed, the engine seized. The contact stated that the failure had occurred while driving on the highway. No warning lights were illuminated. The contact used a portable diagnostic machine but failed to retrieve a fault code. The vehicle was towed to an independent mechanic, where it was diagnosed with engine failure. The vehicle was not repaired. The contact was advised to tow the vehicle to the dealer. In addition, the contact was informed of an unknown recall for the year, make, and model vehicle. 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. In addition, the contact was informed of an unknown recall; however, the VIN was not under recall. The contact was advised to contact the NHTSA Hotline to report the failure. The manufacturer was made aware of the failure but provided no assistance. The contact was informed that the vehicle was purchased used. In addition, the contact was informed that the recall mileage limit was 100,000. The failure mileage was approximately 99,325.
Engine, Dec 10, 2025
The contact owns a 2015 Kia Optima. The contact stated that while driving at an undisclosed speed, the engine seized. The contact stated that the check engine warning light was illuminated several minutes before the engine seized. The vehicle was towed to an independent mechanic, where it was diagnosed with engine failure. The contact was informed that the engine needed to be replaced. The vehicle was not repaired. The vehicle was then 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 contact was informed that the repair was not covered under warranty. The manufacturer was made aware of the failure but provided no assistance. The contact was informed that because the previous owner did not have an unknown software update performed, the repair was not covered under warranty. The failure mileage was approximately 138,000.
Service brakes, Hydraulic, Engine, Dec 3, 2025
The contact owns a 2015 Kia Optima. The contact stated that while driving at 40 MPH, there was an abnormal knocking sound coming from the engine. No warning light was illuminated. The vehicle was taken to the dealer, where it was diagnosed with engine failure, and the contact was informed that the engine needed to be replaced. The contact stated that the dealer refused to repair the vehicle. The contact was informed that the HECU recall repair needed to be completed first. The contact was unaware that the vehicle was included in NHTSA Campaign Number: 21V331000 (SERVICE BRAKES, HYDRAULIC). The vehicle remained at the dealer unrepaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 77,000.
Electrical system, Engine, Dec 3, 2025
The incident took place on Sunday, December 30th. I was driving to pick up my children from their father and on our way home my car stopped accelerating entirely. This had only happen one other time a few days prior. I was in a gas station parking lot and initially when I turned my car on and went to put it into drive it wouldn’t accelerate. I thought that was odd so I did the only thing I knew how to, I checked my oil levels. Levels were full and no other issues were there. The check engine light had popped up when I turned my car back on but my car did accelerate so I thought nothing of it. I took my car to auto zone for a diagnostic and they told me my “B cam shaft” sensor needed to be moved and that could be causing the engine light to come on and ticking in my motor. I called a few shops getting quotes and eventually was forced to tow to the closest shop to me after my car refused to start overall. They replaced the battery and the b cam shaft censors and still were unable to get the car started. They told me 3 recalls were open on my car, including the motor and to have it towed to Kia for a full replacement. After calling Kia to have the repairs done, they refused me service based on a previous owner not handling prior recalls.
Engine, Fuel/propulsion system, Dec 2, 2025
12-01-2025 driving to work in the morning approx 7:00A.M. and turned on the heater and had a very strong smell like fuel so immediately turned it off. Cracked my windows to air it out and then was super cold again and had turned on the heater to try again. Immediately had to turn it off and rolled windows down to air it out because the smell was intense and had started to feel nauseas. Later in the day, about to head to lunch and had started the vehicle and smelt a lot like gas and turned it off and had someone come out to double check the smell. Co worker had strong smell from the hood area and looked underneath the car and can see a little drop puddle. Opened the hood and lifted the cover to engine where you can see the leakage coming from the center hose and spill puddle. Service tech came to take a look and advised its the fuel feed to the high pressure pump. This is a safety concern because fuel is extremely flammable and can put myself in dangerous situation of firing igniting in the car or hurt others around. No check engine light and prior the vehicle incident car has been consuming oil putting in about 1- quart a week or so with commute miles about 270 weekly.
Power train, Engine, Fuel/propulsion system, Nov 23, 2025
While driving my 2015 Kia Optima (VIN: [XXX] ) at highway speed, the engine suddenly shut off without any warning lights, alerts, noises, or check-engine indicators. This created a dangerous situation for me and surrounding drivers. The vehicle had passed state inspection only 3 months earlier with no issues. The sudden shutdown is consistent with the known Theta II engine defect investigated by NHTSA. The car is now completely undrivable. Two Kia dealerships refused to assist, claiming that they cannot perform KSDS because the engine is already dead. These reasons directly contradict the Kia Theta II engine settlement terms. This sudden stall is a safety hazard and could have caused a severe crash. I am requesting that NHTSA review this incident as a potential recurrence of the engine-stall defect already documented in Hyundai/Kia vehicles. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
Engine, Oct 21, 2025
My engine failed in my 2015 Kia Optima. I took it to the Kia dealership in my city, and was advised to provide documentation of oil changes. In which I did, and was told that coverage for the engine recall was denied due to one gap where I went roughly 15,000 miles without an oil change. When asked when this gap was, they stated in 2021, and I asked how can I get documentation of that if I don’t have the receipt from that long ago. They stated that they need documentation to be able to approve the engine to be covered under the recall. it has been advised that Kia would have to prove exceptional neglect, in which one gap from 2021 is not exceptional neglect. I called the Kia. Customer service complaint line and filed a complaint with a case number, and was told that there’s nothing they can do without that documentation from that one gap. In which I asked to escalate this to a manager or supervisor and was told I could not do that. when I called the Kia dealership to see options, all they kept doing was trying to persuade me to just buy a new car asking don’t you just want a new car. I am without a vehicle and I have two kids that I need to help get to and from school doctors appointments as well as after school activities. I do not believe that a one gap should disqualify you from coverage of an engine under the recall.
Electrical system, Engine, Oct 14, 2025
All recalls were not done false input information they never fixed engine bearing recall I’m getting a consultant to handle all the false information being provided by Kia Federico in woodriver
Engine, Oct 10, 2025
I experienced a sudden engine failure on the highway due to the known Theta II engine defect. The engine completely shut down in the middle of traffic, nearly causing a serious accident. I never received any notice from Kia regarding the KSDS (Knock Sensor Detection System) update or any engine recall programs. When I contacted Kia Consumer Affairs, they told me they would not cover the engine replacement because the KSDS update was not installed prior to the failure. Kia admitted that the notice was sent to the previous owner, not to me, even though I am the current registered owner of the vehicle. I was never given the opportunity to install the software update or address the defect before this dangerous failure occurred. Kia representatives also stated that KSDS “was not a recall, only part of a class action lawsuit,” and therefore they are not obligated to cover the engine. This is misleading. The underlying Theta II engine defect was subject to NHTSA investigations and multiple recall campaigns. The sudden engine shutdown on a public highway created an immediate safety risk for me and other drivers. I am filing this complaint because Kia is denying coverage for a federally recognized engine defect due to their own failure to notify the current owner. I am requesting that NHTSA review Kia’s handling of this defect and their use of KSDS as a barrier to coverage. Their failure to notify current owners has resulted in dangerous, potentially life-threatening vehicle failures.
Engine, Oct 8, 2025
9/25/2025 - our vehicle suddenly stopped in the middle of a busy roadway creating a hazard. We had it towed to [XXX] Kia of Greenville. 9/26/2025 we were advised that the engine had seized with no symptoms and no warning lights. The technician said that it would be covered under the vehicles extended warranty due to the known defect/class action on the Theta II GDI engine documented here: [XXX] 10/2/2025 we were advised the car would NOT be covered under the warranty due to some conflict on a CarFax report. according to CarFax, the vehicle has 82k with 15 maintenance records. This was not a case of neglect by the owner, it is a known defect that Kia is not willing to fix. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
Electrical system, Engine, Fuel/propulsion system, Oct 4, 2025
While driving my 2015 Kia optima I was getting ready to turn in to my residence.My car completely shut off but my lights had got dimmed.So I had it towed to the Kia dealership then proceeded to tell me it has three recalls on it.Then a customer service representative said that I would have to pay $200,and something dollars to have my car diagnostic done.Whoever I replied even with these recalls I have to pay for diagnostic test to be done she replies yes,but I’m thinking they are just trying to make money off customers.
Engine, Sep 29, 2025
My engine recently sustained damage. Although my vehicle’s VIN is listed in the affected recall range, I never received any safety recall notification. I purchased the car in January 2024 while the KSDS recall was still active, yet no one informed me of the recall at the time of sale and I have received no updates since.
Engine, Sep 26, 2025
The engine in my 2015 Kia Optima Hybrid failed due to a known defect with the 2.4L engine used in Kia and Hyundai vehicles. The vehicle suddenly quit running and has been inoperable since. Prior to failure, the car had exhibited knocking noises and loss of power. This placed my safety at risk as the vehicle stalled unexpectedly and could have caused an accident if it occurred in traffic. The failure has been confirmed by an independent mechanic, who diagnosed the engine as needing complete replacement. Kia has refused to cover the repair, stating that the vehicle is past the extended warranty mileage, even though the issue is consistent with widely reported manufacturing defects on this engine family. The engine is still available for inspection, and there were no warning lights before the sudden failure. This problem has been widely reported by other Kia owners but my vehicle’s VIN is not included in the current recall campaign, leaving me with a non-functional vehicle despite the same defect.
Engine and engine cooling, Sep 26, 2025, fire
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.
Engine, Sep 24, 2025
The contact owns a 2015 Kia Optima. The contact stated that while driving at 35 MPH and attempting to accelerate, the vehicle entered LIMP Mode, lost motive power, and was unable to accelerate above 30 MPH. The contact was able to pull over to the shoulder of the roadway to turn off the vehicle; however, the vehicle failed to restart. Several unknown warning lights were illuminated. The vehicle was towed to the dealer, who diagnosed a failure with the engine. The contact was informed that the engine needed to be replaced, and the repair could not be covered by the manufacturer because the vehicle had not received the Knock Sensor Detection System (KSDS) ECU upgrade (PI2002D) prior to the failure. The vehicle was not repaired. The manufacturer was notified of the failure, and a case was opened. The failure mileage was 58,000.
Engine, Sep 23, 2025
The contact owns a 2015 Kia Optima. The contact stated that while driving at an undisclosed speed, the vehicle lost motive power. There was no warning light illuminated. The vehicle was not able to restart. The vehicle was towed to the residence. The dealer was not contacted. The vehicle was diagnosed or repaired. The manufacturer was made aware of the failure. The approximate failure mileage was 127,000.
Engine, Sep 18, 2025
The contact owns a 2015 Kia Optima. The contact stated while driving approximately 65 MPH, there was an abnormal knocking sound coming from the engine compartment before the vehicle stalled. The vehicle was towed to the local mechanic who diagnosed and determined that the engine had failed and needed to be replaced. The manufacturer was notified of the failure and advised the contact to tow the vehicle to a local dealer for assistance. The vehicle was towed to the local dealer but was not repaired. The failure mileage was 60,000.
Engine, Sep 16, 2025
Ive had a recall once before got it fix . Few months later it started smoking from exhaust pipes smoke was white . Took it to kia shop they had told me it was a gasket . Ever since then it has been sitting and ive been paying payments for something i can not drive and for a car i keep having recalls and problems with and I need fix . Kia should have a recall on all motors for 2015 as well . But something needs to be done . Been nothing but issue after issue .
Other or unspecified, Engine, Sep 12, 2025
The car just shut off