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definitely annoying
Crashes / Fires:
0 / 0
Injuries / Deaths:
0 / 0
Average Mileage:
33,869 miles

About These NHTSA Complaints:

This data is from the NHTSA — the US gov't agency tasked with vehicle safety. Complaints are spread across multiple & redundant categories, & are not organized by problem.

So how do you find out what problems are occurring? For this NHTSA complaint data, the only way is to read through the comments below. Any duplicates or errors? It's not us.

2012 Kia Optima drivetrain problems

drivetrain problem

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2012 Kia Optima Owner Comments

problem #14

Sep 202016


  • 96,789 miles


While driving approximately 65 mph on a highway, the engine shut down without warning. The vehicle was coasted to the side of the road but would not restart. It was towed to a mechanic who diagnosed a catastrophic engine failure. The shop maintained that the engine seized due to apparent improper oil change. The vehicle was purchased less than 30 days prior to the event. The vehicle was subsequently towed to a Kia dealership where they, too, were unable to manually turn the engine over. Kia service center removed the valve cover and found heavy sludge built up in engine causing it to fail and lock up. Kia motors of America denied claim due to lack of proper maintenance. However, Hyundai sonata engines were recalled due to metallic debris in engine which restricted oil flow and presented the same manifestations of engine sludge. Kia Optima sedans were built using engines manufactured at the plant cited in the Hyundai recall.

- Falls Church, VA, USA

problem #13

Apr 052016


  • 73,000 miles
I have a knocking sound in my steering wheel. The noise happens when I turn the wheel back and forth. Also, I have noticed an odd grinding/slipping sensation in the front left wheel when I accelerate on a right turn from different elevations. Pulling out of a parking lot on a "decline" while accelerating to the right to enter traffic is a good example. 73,000 miles currently but I've noticed the grind/slip a lower mileage.

- Fort Myers, FL, USA

problem #12

Jul 022015


  • 61,000 miles
Car will jerk hard when changing gears. It happens while going in speeds below 45 mph. The car will jerk really hard while driving and the rpms will jump from 2-3 straight up to 6. it has happened several times in the last week. I am taking it to the Kia dealer to see if they can locate and fix the problem. Based on what I have read here, there doesn't appear to be a fix. I am really concerned it will accelerate and cause me to have an accident.

- Durham, NC, USA

problem #11

Apr 232015


  • 34,945 miles


Jerking and loss of acceleration when driving and when shifting in parking/reverse. When shifting in reverse it makes a jerk and make a thud. Same thing in drive but a little more harsh. Jerking also just when shifting to drive after starting the car. Even when I drive it would give a jerk a few times when switching gears, and also when I brake to slow down it does it. I also remember the car shaking one time when I turned it on. It also lost acceleration while driving to work in a 45 mpg area. Had to pull over and shut/restart the car a few times. Taken in to Kia each time this happened. Last night, June 30, was the forth time. Kia can't figure out what's wrong with it. It is scary and unsafe as I feel it can cause a rear-end accident.

- Buena Park, CA, USA

problem #10

Sep 022014

Optima 4-cyl

  • 59,000 miles
The waste gate actuator on Kia Optima turbo model failed. There are thousands of complaints about this defective part online and Kia has not address the issue of this defect. To replace the defective part which is not covered under the powertrain warranty is $500. Do not purchase a Kia until they have addressed this glaring defect. I've had 8 cars in my life 7 Honda and 1 Kia. The Kia was a big mistake.

- Allentown, PA, USA

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problem #9

Feb 122014

Optima 4-cyl

  • 42,000 miles
Vehicle had random abnormal jerking, bucking and clunking by the transmission during normal acceleration, which causes abnormal deceleration. This could cause an issue with normal driving and can cause a rear end accident. The cause of this after vehicle was taken to the dealer, is the transmission temperature relay. Apparently the mechanic advised that other vehicles have been brought in with the same relay issue and there has been no recalls on the part.

- Kissimmee, FL, USA

problem #8

Jun 052013


  • 62,609 miles


While driving my 2012 Kia Optima sx T gdi I lost accelerations on the highway. I was driving at 55 mph because the car wouldn't accelerate, but it did decrease in speed to a dangerous 20 mph. I tried to use my paddle shifters in hopes that would work, to no avail. I depressed the gas pedal to the floor and the speed did not change. I eventually reached a safe place and shut the car off, waited several minutes and attempted re-starting the car. The car sputtered and paused before eventually starting, then allowed me to drive approximately 100 yards before having the same decreased speed situation again. I was fortunate to drive home at 45 mph and avoid being run off the rode or rear ended by another vehicle or worse... a truck. The next morning I took the car to the dealership and after a diagnostic was informed that the fuel pressure sensor needed to be replaced. Not such bad news but I was shocked that the price quoted to me, by the service manager, is $900. Unbelievable!!! I searched all over the internet and found all the parts that are related to this type issue and nothing, not one part, cost $900. The proposed cost to repair my car is greater than the car payment. As a matter of fact, it cost more than the car payment for my wife's ML500. I have visited Kia forums that speak to problems with the Kia and it seems that a manufacturer is in order. Incidentally, the part is no longer covered by the warranty because I recently passed the 60,000 mile mark. I feel like I am being ripped off to have the car repaired for what will be less than an hour of work to replaced a minor part, that incidentally has a cost of $900. I will be willing to provide any other additional information related to my experience with my 2012 Kia Optima. I should be purchased and Audi.

- Penryn, CA, USA

problem #7

Apr 022012

Optima 4-cyl

  • 150 miles
Steering is very unstable. Extremely afraid of this car - I feel like I am not in control when driving, I constantly have to fight to stay straight. Veers/pulls left and right as if im bouncing in between the lines on the interstate. My stomach stays in knots in fear I will hit another vehicle, or worse a concrete barrier in the construction on the interstate. It feels as if 3-5 seconds I am not in control, my arms are exhausted by the time I arrive to my work, home, or elsewhere. Have complained several times to Kia dealer when having oil changed & I am always told nothing is wrong or cannot duplicate problem. Four mechanics have driven my car elsewhere and agree there is a safety issue and Kia should recall and fix before it cost someone/a family their lives. My dash lights also surge to maximum brightness at any random moment while driving - all on their own. I recently started having issues with starting my car, I bought my car in March 2012 and currently have 14K miles (highway for work). Recently, twice my car felt as if it was not going to start, sputtering, smell of exhaust inside car. I also have issues if I am at a red light/stopped and when I accelerate sometimes the car feels as if it dies out for a second - misfiring. I can not pass in traffic out of fear my car will not respond when I try to accelerate. My car constantly will not connect to my phone, or keeps a call display on the radio after the call has ended (freezes) until I restart my car. I feel there is something terribly wrong with the wiring/electrical/steering with my car and several others according to other complaints on here! Toyota recalled only after a death, Hyundai/Nissan/Dodge all just recalled immediately - what about us Kia? I have a family in this sedan that is going to end up costing my life or worse, my entire family's lives! please address this problem!!!!! steering is not normal or safe!!!

- Gonzales, LA, USA

problem #6

Nov 162011

Optima 4-cyl

  • 500 miles
First thing car was not shifting gears. Dealer replaced transmission. Second occurrence pulled out and car lost power was able to pull off road turn ignition off and restarted car was ok. Dealer replaced engine control module. Next occurrence Nov 2012 car did same thing restarted was ok engine light went off after 2 days. Now Jan 2013 cold morning started driving engine had no power. I got to a open road slowly pushed accelerator to floor with no response. Car is now in dealership I'm waiting for my phone call.

- Reading, PA, USA

problem #5

Sep 112012


  • 16,000 miles
The contact owns a 2012 Kia Optima. The contact stated that while driving 70 mph, there was a grinding noise coming from the front driver's side of the vehicle. The vehicle was taken to the dealer and after inspection, they informed her that the front axle shaft detached from the transmission. The technicians removed and replaced the right axle shaft, and also reassembled and re-tested the vehicle. The contact stated that the failure recurred twice. The manufacturer was not notified. The failure mileage was 16,000.

- Grand Forks, ND, USA

problem #4

Dec 102012


  • 12,620 miles


After warming up engine I drove onto the road and onto a freeway entrance Ram a quarter mile from my home. While entering the freeway, the car "lost power", ie no throttle response, car would not go faster than 60 mph. RPM was peaking over 3,000 RPM (higher than normal). I put the auto/manual floor-shift into manual and the dash showed 4th gear. I shifted back and forth between auto and manual with the same results several times, 4th gear, over 3,000 RPM, loss of power (no throttle response), max speed 60 mph. I nearly got rear ended, cars were dodging me. I was about to pull off the road and everything returned to normal. I read a similar report a few months ago from another "new" owner of an Optima and the dealership "couldn't find" anything wrong. I now have read lots of warranty-denied horror stories with Kia. This seems like a transmission problem. I imagine it could be a "computer problem" as there are lots of computers in these new cars. I can't find any tsb's listed for transmission related problems, but am wondering how many others have this "elusive" condition?

- San Diego, CA, USA

problem #3

Sep 132012

Optima 4-cyl

  • 1,350 miles
While driving approximately 25mph I heard a loud 'bang'. shortly thereafter, my Optima would periodically shift gears very roughly on downshifts. There was also a 'clanking' noise present on the rough downshifts or when the Optima was shifted into reverse. Upshifts while accelerating seemed to function normally. I immediately brought the car to the dealership where it was purchased. The dealership determined a bolt had snapped on the transmission mount causing the transmission to knock into the engine when it shifted. It was the belief of the dealership that the bolt had been under torqued when it was assembled in the factory. The subframe and a dented piece of the exhaust had to be replaced. This seems very dangerous to me, especially had it occurred on an expressway at a high rate of speed.

- Frankfort, IL, USA

problem #2

Dec 232011


  • 400 miles
The contact owns a 2012 Kia Optima. The contact stated that when the accelerator pedal was depressed the rpms revved abnormally high but the vehicle failed to accelerate properly. The vehicle was taken to the dealer. The manufacturer was made aware of the failure. The vehicle was not repaired. The failure mileage was 400 and the current mileage was 10,500.

- Fort Lauderdale, FL, USA

problem #1

Aug 082012


  • 13,800 miles
Was sitting at light and went to take off car felt like it didn't want to shift into gear and had a loud rough grinding noise, all lights on the dashboard came one. Brake light, check engine light, coolant, etc and none of the gauges were working. I stopped at the store and went to leave the car would start up but wouldn't go into gear, it was stuck in park. I had to get it towed to the dealership to have it looked at. I had just had this same problem 1 week ago where all the lights were on and the gauges weren't working and the dealership had supposedly replaced the fuse panel box but that apparently didn't fix the problem. I think that it's a computer or engine issue.

- Mcdonough, GA, USA

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