Which parts fail
Components named in complaints (automatic and manual transmissions, CVT, axles, driveshaft, 4WD/AWD).
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 stated that while parking the vehicle, the gear shifter was shifted into park; however, the message to shift to park was displayed. In addition, the contact stated that there was a delay while shifting gears. The vehicle was taken to the dealer; however, the failure was not duplicated. The contact stated that the vehicle was taken to several dealers, and the failure was not duplicated. The contact was informed by one dealer that the transmission needed to be replaced. The vehicle was not diagnosed or repaired by an independent mechanic or dealer. The contact researched and determined that the failure was related to the TCM failure. The manufacturer was made aware of the failure. The failure mileage was approximately 78,000.
The contact owns a 2012 Kia Optima. The contact stated that while driving at various speeds, the vehicle hesitated while depressing the accelerator pedal. The check engine warning light eventually became illuminated, and the vehicle was taken to an independent mechanic to be diagnosed. The mechanic retrieved a fault code for the engine variable valve timing solenoid. The contact was informed that the engine variable valve timing solenoid needed to be replaced. The contact called a dealer and was informed that there were no recalls on the vehicle for the failure. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 130,000.
The contact owns a 2012 Kia Optima. The contact stated while driving at 55 MPH, he heard an abnormal grinding sound coming from the engine. There was no warning light illuminated. The contact was able to continue driving. The contact stated that the failure had been reoccurring while driving. The vehicle was taken to the dealer where it was diagnosed that the transmission had failed and needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure and informed the contact that they could not assist as the warranty had expired. The failure mileage was approximately 45,000.
The shifter cable came off during the car was on motion in my driveway..and unable to put it in PARK. My driveway has quite inclining uphill.. imagine if the car would roll back .. or simply the fact it worries me if that could happen somewhere away i would totally get stranded.. upon google i was able to confirm that KIA using the cheap parts and this happened to others also.. My boyfriend was able open gear console cover and snapped the cable ring back ...KIA should replace this part ASAP. BTW .. this was the second time it happened within a year
Power train and engine failure and causing my Kia to catch on fire at 11:30 coming back home from work. I was Driving home and smell smoke and car was shaking and when I stopped at the highway to open and look fire was on while driving and I had to call 911 and stop the fire. I had some fire extinguisher in the car I stopped the fire and towed the car and I replaced engine and powered train For over $9000 between repairs and labor and transmission and engine
Subject: RECALL VIOLATION: Kia on the Boulevard (Philadelphia) - Refused Remedy, Charged $199, Returned Unsafe Vehicle Vehicle Information: [Year] Kia Optima Hybrid Dealership Name: Kia on the Boulevard Dealership Address: 11295 Roosevelt Blvd, Philadelphia, PA 19154 Complaint Description: 1. The Safety Incident: While operating the vehicle, I experienced a catastrophic engine failure. Thick smoke poured from the engine compartment, followed by immediate stalling. This presented a severe fire risk and safety hazard. 2. Dealer Misconduct & Illegal Charges: I towed the vehicle to Kia on the Boulevard (11295 Roosevelt Blvd, Philadelphia) for the active engine recall remedy. The dealership: * Refused to perform the recall repair free of charge. * Forced me to pay a $199 "diagnostic fee" just to look at the recall-related defect, which should be covered by the manufacturer. …
My engine failed. Dick Withams here in Waterloo, IA was paid by Kia to replace engine for free due to my warranty. Dick Withams rushed the process and allowed me back on the road with no coolant plug( which was detected immediately) I returned the car and Dick Withams attached a plug so my coolant wouldn't spill over on the ground. Every time I pressed my brakes THERE WAS A HORRIBLE SOUND LIKE MY DRIVE AXIAL WAS NOT PUT TOGETHER WHEN Putting the engine back. Kia is allowing Mechanics to fix these recalls of MAJOR SAFETY ISSUES FOR myself and my family. I then returned vehicle to Cedar Falls, IA Dick Withams to fix issue Friday morning. They have yet to communicate anything with me. Now I'm just without a vehicle even though it's covered under warranty. …
My wife had been complaining that while driving 2011 optima hybrid at highway speeds the car would suddenly lose power and slow to 30 or 40 mph while the pedal is floored. Took it to the dealer who said we needed a new battery which did not solve the problem. 2nd time came with a warning on the dash to check hybrid system, back at the dealer they said it appears to be some special fuse in the trunk ($300)...problem sill persist however this time the car completely shut down on the road, dash was lit up like a Christmas tree. Had to get it towed. Now dealer says its the HPCU and that's going to run almost $6000. Dealer was willing to install a used one i got on EBay, they charged $1300 for the install they tell me the problem still exists.
Sudden engine failure while driving with no warning. Vehicle began jerking, shaking, and losing power. RPMs dropped unexpectedly and the engine stalled intermittently. Multiple misfire codes were present (cylinders 1, 3, and 4), and the engine was found to have low or no compression in cylinder 1. The condition rapidly worsened to near complete engine failure. The vehicle was operating normally prior to this incident. This failure is consistent with known Kia engine defects involving internal engine damage, including rod bearing failure. This is a safety concern due to sudden loss of power while driving.
The failure involves the component covered under the active safety recall campaign. The affected part/system is still installed on the vehicle and is available for inspection upon request by the manufacturer, dealership, or NHTSA. Recall number : 23V6552 While driving in traffic, the vehicle suddenly began to slow down without warning, started jerking, and lost normal operation. I was forced to pull over to avoid a collision. This sudden loss of power and control placed me, my passengers, and surrounding drivers at risk of an accident. Yes. The issue was confirmed by an authorized dealership. The dealership acknowledged that the problem is directly related to the active safety recall but refused to perform the repair due to vehicle mileage exceeding 150,000 miles. The vehicle has been inspected by an authorized dealership representing the manufacturer. …
Transmission complaints in other Optima years
Frequently asked questions
How common are transmission problems on the 2012 Kia Optima?
NHTSA has 54 complaints about the transmission & drivetrain of the 2012 Kia Optima, 6% of the model year's 920 complaints. The component named most often is automatic transmission › lever and linkage › floor shift (1 mentions).
Is there a recall for 2012 Kia Optima transmission problems?
No. NHTSA lists no transmission & drivetrain recall for the 2012 Kia Optima, though it has 5 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2012 Kia Optima transmission problems start?
Half of the complaints with a recorded mileage happened before about 80,000 miles, and 17% before 25,000 miles.
Is it dangerous?
Owners linked 1 crash, 1 fire and 0 injuries to transmission & drivetrain 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.