Which parts fail
Components named in complaints (engine, cooling system, oil leaks, timing chain, exhaust).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2012 Kia Optima owners, lightly cleaned up (personal details are redacted by NHTSA).
The contact owns a 2012 Kia Optima. The contact received notification of NHTSA Campaign Number: 23V652000 (Service Brakes, Hydraulic) however, the part to do the repair was unavailable. The contact stated that the manufacturer exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The contact had experienced a failure. The contact stated that his wife was driving the vehicle at approximately 35 MPH when she was she flagged by another driver that her vehicle was emitting flames under the vehicle on the front driver's side near the wheel well. The contact stated his wife was not aware of any warning lights and pulled the vehicle over and stopped. The contact stated the fire department was on scene and extinguished the fire. The vehicle was towed to a local dealer, the contact had no information on the diagnosis by the dealer. …
The contact owns a 2012 Kia Optima. The contact stated while at a complete stop at the traffic light, she noticed that there was smoke coming from underneath the driver's side of the hood. Additionally, the vehicle stalled and failed to restart. The check engine warning light was illuminated. The contact exited the vehicle. The contact stated that there were flames coming from underneath the hood. The fire department extinguished the fire but declined to provide a copy of the report to the contact. No police report was filed. There were no injuries sustained. The vehicle was pushed into a parking lot. The vehicle was then howled to the residence the following day. The dealer was notified of the failure. The vehicle was not diagnosed or repaired. The contact related the failure to NHTSA Campaign Numbers: 23V652000(Service Brakes, Hydraulic) and 17V224000(Engine and Engine Cooling). …
The contact owned a 2012 Kia Optima. The contact received notification of NHTSA Campaign Number: 17V224000 (Engine and Engine Cooling). The contact stated that while driving at 30 - 35 mph, the vehicle loss motive power without warning. The oil warning light was first illuminated then all of the warning lights were illuminated. The contact was able to pull over on the side of the road. The contact tried to restart the vehicle when she detected a smoke odor and saw there was smoke coming from under the hood. The contact exited the vehicle with her daughter. The contact then opened the hood and saw that the engine had caught fire. The contact had a friend from nearby come help to put out the fire with water. No medical attention was received. No police report was filed. The vehicle was not diagnosed nor repaired and remained on the side of the road. …
The contact owns a 2012 Kia Optima Hybrid. The contact stated while driving 50 mph when a noise coming from the engine compartment was heard and saw smoke emitting from the engine compartment. The contact pulled over and upon investigation, a fire was underneath the engine compartment. The contact waited until the fire was extinguished naturally and the fire department was not called. The contact stated the check engine warning light was illuminated. The vehicle was towed to contact's residence. The vehicle was then towed to a local mechanic where it was confirmed that the engine caught fire and was repaired. Upon investigation, the contact associated the failure with, NHTSA Campaign Number: 20V750000 (ENGINE) however the VIN was not included. The manufacturer was not informed of the failure. The failure mileage was approximately 13,000
The contact owned a 2012 Kia Optima. The contact stated that while at a stop light, smoke and flames were suddenly present coming from the engine compartment. The fire department was called to the scene and extinguished the fire. During the incident, the vehicle was destroyed and later towed to an inbound facility. No report was taken and no injuries were reported. The cause of the fire was not determined. The local dealer and manufacturer were not yet contacted. The contact was informed that the VIN was included in the NHTSA Campaign Number: 23V652000(SERVICE BRAKES, HYDRAULIC). The contact indicated that the vehicle had experienced that same failure listed in the recall. The failure mileage was 151,000.
After the rod bearing engine replacement was preformed. My engine light came on a few days after picking it up from dealer. I immediately reported it to the dealer that I need to bring it in mainly for smog check, and no response. 2 weeks later I told them about it again. No response. 3 weeks later began a fuel smell and I immediately reported that as the smell got stronger. No response. 3 days later the fuel smell was really bad and I was really worried about a fire. This time I called general manager and he never provided any advice or return call. 3 hours later the engine caught on fire. Car is totaled and I could of been seriously injured. I sent pictures and thanked them for their negligence. He finally gave me a phone number for consumer affairs. showed no remorse and claimed that the new engine they just put in has no warranty and they are not responsible. …
The contact owns a 2012 Kia Optima. The contact stated while driving approximately 70 MPH, the check engine warning illuminated, and the vehicle lost motive power. The contact stated that the engine was running however, the vehicle failed to respond as needed. The contact pulled off the highway into a rest area. The contact stated that the engine and the vehicle were shaking abnormally. The contact turned the vehicle off and noticed gray smoke coming from underneath the hood on the driver's side near the windshield. The contact stated that he opened the hood and checked the fluid levels, and the oil and coolant were at normal levels. The contact restarted the vehicle and the vehicle started to shake. The contact shifted into drive(D) and depressed the accelerator pedal, but the vehicle failed to respond as needed. The contact had the vehicle towed to an independent mechanic. …
The contact owns a 2012 Kia Optima. The contact stated while driving at various speeds, the vehicle went into LIMP Mode and failed to exceed 61 MPH. The RPM failed to exceed 2,000 RPM. Additionally, the contact stated that the vehicle failed to exceed 45 MPH while driving uphill, and the vehicle failed to exceed 55 MPH while driving downhill. The contact scanned the vehicle with a vehicle scanner and retrieved codes indicating an oil control valve failure. The contact replaced the oil control valve; however, the failure recurred. The vehicle was taken to the dealer where the fuel rail system, the fuel tube clamps, and the bolts were replaced under NHTSA Campaign Number: 18V907000 (Fuel System, Gasoline, Engine); however, the failure persisted. The vehicle was taken back to the dealer several times. …
The contact owns a 2012 Kia Optima. The contact stated while her grandson was driving at approximately 35 MPH, the vehicle started hesitating before the vehicle stalled in the middle of the roadway. The driver was able to restart the vehicle after several attempts, but the vehicle was idling rough. The contact stated that the near-stalling failure had occurred several times. The contact stated at the recent failure the check engine warning light was illuminated. The contact had not taken the vehicle to a local dealer or independent mechanic. The vehicle was diagnosed by the contact's son-in-law who retrieved DTC: P1326 (Engine). The vehicle had not been repaired. The contact stated that the failure was related to NHTSA Campaign Number: 17V224000 (Engine and Engine Cooling). The manufacturer had not been informed of the failure. The failure mileage was 77,210.
The contact owned a 2012 Kia Optima. The contact stated that while driving 60 MPH, the vehicle jerked, with an abnormal hissing sound coming from the front of the vehicle. The contact stated that there was smoke coming from the rear of the vehicle and entering the cabin of the vehicle through the A/C vents. The contact stated that several warning lights were illuminated. The contact pulled over to the side of the road and the vehicle was towed to an independent mechanic. The contact was informed that there was a hole in the engine. The contact was informed that the engine needed to be replaced. The vehicle was not repaired due to the cost. The manufacturer was not notified of the failure. The contact notified the insurance company; however, no claim was filed. The failure mileage was approximately 160,000.
Related recalls
Engine
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.
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.
Engine and engine cooling › Engine
Kia Motor Company (Kia) is recalling certain 2011-2014 Optima, 2012-2014 Sorento and 2011-2013 Sportage vehicles. Machining errors during the engine manufacturing process may cause premature bearing wear within the engine.
Remedy: Kia will notify owners, and dealers will inspect the engine assembly, and replace the engine if necessary, free of charge. The recall began June 20, 2017. Owners may contact Kia customer service at 1-800-333-4542.
NHTSA investigations
Scope and Timeliness
NHTSA opened Recall Query (RQ) 17-003 to investigate the timeliness and scope of Kia?s Theta II GDI engine recall (Recall No. 17V-224), and Kia?s compliance with reporting requirements. On November 23, 2020, the Agency entered into a Consent Order with Kia to administratively resolve NHTSA?s assertions of violations of law in connection with RQ17-003.
Engine Fires
On March 29, 2019, the Office of Defects Investigation (ODI) opened two Preliminary Evaluations (PE19-003 on Hyundai and PE19-004 on Kia) to broadly investigate incidents of non-crash fires (regardless of origin or operational status of the vehicle) on various model year Hyundai and Kia vehicles.
Loss of Motive Power
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.
Engine complaints in other Optima years
Frequently asked questions
How common are engine problems on the 2012 Kia Optima?
NHTSA has 416 complaints about the engine & cooling of the 2012 Kia Optima, 45% of the model year's 920 complaints. The component named most often is engine › gasoline › turbo/supercharger (1 mentions).
Is there a recall for 2012 Kia Optima engine problems?
Yes — NHTSA recall 18V-907 (engine, Dec 19, 2018); NHTSA recall 17V-224 (engine, Mar 31, 2017). Recall repairs are free at authorized dealers.
At what mileage do 2012 Kia Optima engine problems start?
Half of the complaints with a recorded mileage happened before about 100,000 miles, and 9% before 25,000 miles.
Is it dangerous?
Owners linked 4 crashes, 62 fires and 5 injuries to engine & cooling problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.