Which parts fail
Components named in complaints (accelerator pedal, throttle, sudden acceleration, cruise control).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2014 Kia Optima owners, lightly cleaned up (personal details are redacted by NHTSA).
engine was replaced per CASE # 14397135, and PI1803Y/Z, SINCE engine repair Turbocharger Boost Control Position Sensor "A" Circuit High CODES (P2562 & P2565) continuously come and go. Check engine light comes on and off for the same codes. Knocking noise continues, loss of acceleration as if voltage or gas was lost, steering wheel speed control buttons (+/-) no longer properly function since engine replacement. It now has a class 2 leak. Safety risk:when driving it loses speed or fails to accelerate may cause crash. KIA dealership has tried to access the code but Codes are spontaneous, same for loss of acceleration.
I was driving down the interstate for my work commute apx 70 mph when HEV warning light engaged and vehicle went into limp mode. Had vehicle towed to dealership after running several tests determined the engine was knocking and needed replaced. After 2 months reman engine placed in vehicle. Vehicle function apx 6 months when the exact same problem occured on the highway traveling apx 60 mph. Vehicle is still in dealership. Thankfully, both times I was able to coast to the shoulder and avoid a collision. There is something wrong with these vehicles that need to be fixed.
Vehicle has engine failure at 156600mi. Bearings and axle are worn out which caused the engine to go into limp mode (code P1326). Car is accelerating poorly and does not oprate over 60mph. Vehicle required a new engine. Dutch Miller of Charlotte Kia, 7725 South Blvd, Charlotte, NC ensured that engine would be brand new. However, the engine was used, and obtained at LKQ costing $3600. Total cost for the engine and labor totalled $5117.18. Kia also confirmed the problematic suspension which led to the engine failure was fixed. Once again this obligation was not met.
Failed Emissions Test for Engine light being on. Took to mechanic and he specified that it was my gas cap that needed replacing and I did so, but light is still on. No leakage was present at the time when mechanic checked, however, in the past there was a smell of gas inside the vehicle but it's no longer present at the moment.
I was trying to back in between2 vehicles in the church parking lot. And while doing so, with my foot on the brake the car lunched backwards with a jerking motion, like it was trying to do 2 different things atone time, at full rate of speed and doing so, it backed into the vehicle to my left, the car acted like it had a mind of it's own. I reported the accident and when the police arrived on the sight, he informed me that he had seen an issue like this happening on the news. I had never heard of and I went online to report this incident. I was not hurt and if my cousin wasn't in the car, I don't think anyone would've believed me. I think this needs to be looked into, I'm really scared to drive my vehicle.
Tl* the contact owns a 2014 Kia Optima. The contact stated that while driving at 45 MPH, an abnormal odor appeared under the hood. The contact depressed the brake pedal and the vehicle accelerate forward, causing the contact to crash into another vehicle who was making a u-turn. The contact tried to gain control of the steering wheel as the vehicle went up in flames. The contact managed to crash into a ditch. The contact got out ran to the other side of the vehicle where his fianc was unconscious. The contact managed to cut the seatbelt in order to release and drag her out the vehicle. The contact went back to retrieve items but the vehicle then engulfed in flames causing an explosion. The airbags deployed. A police report was made. The fire department extinguished the flames. …
I was driving my car last Friday and the car started accelerating and then slowing down. I tried to speed up when it slowed down because I was in traffic and was afraid that someone would hit me so it would speed up and then slow down. It scared me so I pulled over on a side street so no one would hit me being that the car was driving erratic. I stopped the car, turned it off then restarted it . Once I did that , same thing again so I turned it off again after I pulled over the second time. The 3rd time , it started driving normal but a couple of days later , I could not start it. I had to have towed 3 days in a row to a dealership and they replaced something each day but the next day , the car would not start . I am afraid to get stranded again and this is a brand new car !!! Its a 2014. I was initially real excited when I bought this car because but I have had nothing but problems. …
Tl* the contact owns a 2014 Kia Optima. The contact stated that while the driver was driving at approximately 50 MPH, the air bag warning light illuminated and the cruise control stop functioning. The contact coasted to the side of the road, after a few minutes, the contact was able to resume driving. In addition, the contact stated that while making a right turn into a parking lot there was a rattling noise coming from the interior of the steering wheel. The vehicle was towed to the resident of the contact. The vehicle was taken to an unknown dealer, located on delsea dr, vineland nj, where it was diagnosed that the air bag clock spring cable detached 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 her with the failure and was to go through the vehicle warranty for the repair. …
Crank shaft bearing went bad causing engine to fail in vehicle and almost get hit by traffic contacted dealer and was advised that there was a recall on every model of my car except mine because it was the gas hybrid which still has the same engine and problem as the ones in recall j bought the car for around 13K and only had it for bout 3 months before this happen dealer won't repair work under recall because it does fall under the recall for millions of other because it is hybrid as well as gas ? Doesn't make any sense and I got screwed outta 13K and could have been injured as well as my 2 kids that where in the car with me
I have a Kia Optima 2014 Kia Optima love my car. There's only one bad thing I go do my recall on March 28 2019 it says everything had passed but in reality. The service that they did was careless 9 months later my car is bad motor. Has 130,000 that's what 20,000 dollar is worth wow. They did my oil Kia change they put the wrong oil 5-30 really that for Kia turbo and Kia Optima 5-20 now my car is in a mechanic. I need my car fix , I did my recall thought it was for a cause but I gues it wasn't . I need my car fix ! My car stop in the middle iff the 57 south freeway .. Kia Optima in pomona ca
NHTSA investigations
Throttle control system vulnerabilities
The Office of Defects Investigation (ODI) of the National Highway Traffic Safety Administration (NHTSA) received a petition letter dated October 10, 2021, requesting an investigation of possible defects in the electronic throttle control (ETC) system on certain Kia vehicles resulting in the opening of DP21-003.
Acceleration complaints in other Optima years
Frequently asked questions
How common are acceleration problems on the 2014 Kia Optima?
NHTSA has 21 complaints about the speed control & acceleration of the 2014 Kia Optima, 4% of the model year's 590 complaints. The component named most often is cruise control (1 mentions).
Is there a recall for 2014 Kia Optima acceleration problems?
No. NHTSA lists no speed control & acceleration recall for the 2014 Kia Optima, though it has 7 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 2014 Kia Optima acceleration problems start?
Half of the complaints with a recorded mileage happened before about 62,000 miles, and 23% before 25,000 miles.
Is it dangerous?
Owners linked 3 crashes, 1 fire and 2 injuries and 1 death to speed control & acceleration 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.