2018 Kia Optima

Consuming fuel to the amount of roughly 1/2 quart per 150 miles. Vehicle has been inspected by mechanic and the oil pan, oil filter, and PCV valve has been replaced and engine oil UV dye added and cycled with no leaks found. The risk is that if not rigorously checked often, the engine will malfunction because the car runs out of oil. I have had my mechanic checking this car since I purchased it in January 2026. We have had to replace the oil pan and do two full oil changes with three separate quarts of oil being added in between all of that to keep it topped up. My mechanic agrees that the engine is consuming oil at an extremely high rate. My mechanic and a mechanic at the dealership where I purchased it are the only one who has inspected the car for this issue so far. The mechanic at the dealership is who recommended we replace the oil pan to see if that fixed the leak, which my personal mechanic did. Yes the critical engine failure lamp illuminates on the dashboard when the oil ran out the first time while I was driving it. This was how I discovered that there was an oil leak. This specific incident occurred three weeks after I purchased the car which I bought in mid-January of 2026.

I am submitting this complaint regarding ongoing and persistent mechanical issues with my vehicle since the time of purchase. The vehicle has repeatedly shut off unexpectedly, creating a serious safety concern. Initially, I suspected the issue might be related to the battery, and I have replaced the battery twice within the past 4 years. However, the problem has continued. In January, the vehicle began shaking and shutting down again. I took it to a mechanic, who diagnosed the issue as faulty spark plugs and an ignition coil. The diagnostic codes provided were P0303 and P0456, and the recommended repairs were completed. Approximately one month later, the vehicle began shutting off again. I then took it to the dealership, where I was advised that the valve cover gasket needed to be replaced, along with the belts, and that a fuel system cleaning was required. I subsequently had these repairs completed by my mechanic. Less than a week after completing those repairs, the vehicle once again began shutting down. A diagnostic scan then produced code P123300. In addition to these repeated shutdowns, the vehicle consumes an excessive amount of oil, has poor acceleration, and continues to stall unexpectedly both while driving on the road and while idling, such as in a drive thru. These recurring issues have made the vehicle unreliable and unsafe. I am concerned about the risk of the vehicle shutting off while in motion, which could lead to a dangerous situation. I am requesting that this matter be reviewed for potential defects or safety-related concerns.

About a month ago my paint on my 2018 Kia Optima snow white pearl car started bubbling, then it turned into peeling and has since then been coming off more and more. It is occurring right under the back seat of the drivers side window. Reading into this issue more, it is happening to many who own a Kia Optima owners, especially those who own the snow white pearl color. Kia is not helping customers who are out of warranty but since this is a manufacturer defect they should be, even if they are out of warranty.

I was sold an unsafe vehicle at J and J Auto house 6446 Wilshire Bl LA,CA 90022. Dealer withheld condition of car . Had car three months and was stranded on highway. Car was towed to Kia dealer and diagnosed with complete engine failure. Dealer will not honor limited warranty, shady sales practices withheld recall info during sale, won’t allow his mechanic to look at car, dodged calls, denied request to return car for refund

While driving my 2018 Kia Optima S, the car suddenly jerked, lost power, and stalled in traffic. Multiple warning lights came on at the same time including the oil light, battery light, and check engine light. I had no acceleration and the brakes became very hard to press. The vehicle had to be towed for safety reasons. The Kia dealership inspected the vehicle and confirmed internal engine failure due to “cylinder failure” and stated the engine needs complete replacement. This failure occurred without any external leaks and without warning other than the sudden loss of power. The dealer stated the issue is not covered, even though it is clearly an internal engine malfunction. This is a major safety hazard because the stall happened while I was in active traffic. A sudden loss of power and braking ability puts me and others at risk of an accident. The problem has been confirmed by the Kia dealership through diagnostic testing. The vehicle is still available for inspection. Warning lamps appeared only at the moment of failure, giving no advance warning. This appears to be related to the ongoing engine defects in Kia vehicles involving oil starvation, loss of compression, cylinder scoring, and internal engine failure. Cylinder failure and sudden stalling should be investigated as part of the known safety-related engine defects affecting this model.

Car keeps stalling while driving

Paint peeling from driver side door.

I turned the car off, it had difficulty turning back on and the brake pedal got really hard. I had to wait about 30-45 minutes and then I was able to get the car started and brake pedal back to normal and no lights. Recently, I left the car on to run into a shop real quick and come back out. When I got back to the car, the power steering light, battery, and warning light?(amber triangle with ! In the center of it) were all on. I rev the engine and the issue went away for a quick second but then came back on. To avoid turning my car off and being stuck, I just shift to reverse and tried to leave. I’m backing out of the spot and now the backup camera is going in and out lights flashing on the dash and I’m trying to brake but the brake pedal isn’t registering and next thing you know, I’ve backed into a guard rail. On the way to drop my kids off at the babysitter, I was coming to a stop sign, and my car wouldn’t brake, i went through oncoming trafic and had to run off the road. KIA did a multi point inspection a few months apart from one another. One the car tested fine, then the second time they are saying a brake booster and no engine oil in the vehicle and that the car is basically trash. The oil light goes on and off and I can smell burning oil. I still owe 7 grand on this car and I just bought it last year and it was seamingly fine.

My engine is under the Kia class action lawsuit for the KDS with the rod bearing clearance issues. I have done all my oil changes with paper work available. I got the update to the ECU several years ago as needed to be covered. Now my engine has failed and I took to the dealer to check but they said I didn't have a specific code and that they can't do any testing to verify it would be under the warranty. I called Kia Customer Care and have talked to them several times. They have told me there wasn't a need for the code and that the dealer could do other testing. The dealer stated that they can't do the BCT test due to a cylinder not having compression. I told Kia this is all related to the bearing going out and they said they can't do anything if the dealer said it's not under warranty. So I have now been going in circles with kia and dealer since 11/18/25. I sent kia another email on 12/15/25 and another on 12/18/25 due to not receiving a response. It's now 12/23/25 and still no response. They have a service bulletin that I seen online that was for dealers if any issues with testing they had other options but still nothing has been done.

Steering column coupler went bad. Unable to swap out the coupler alone ($12 part) and had to get a whole new column (over $1200). Some of the Kia's around this one's make and model were recalled but not this one. Without this repair driving would have been dangerous.

Paint on all four door handles are bubbling and chipping. I rarely use the backseat handles and passenger door, which makes it more likely to be a malfunction in whatever paint was used for the handles. There is no fading, chipping, or bubbling on other parts of my car.

I’ve had my car for 6 months and it constantly burns oil I’ve had 4 oil changes because it Is completely disappearing but my mechanics can not find any leaks. Then I changed all my spark plugs and two were completely burnt and they were changed a month ago and now one of them went again and this time is completely covered in oil

I was rearended, all air bags deployed except steeringwheel

Engine seized and stopped working. While I could not find any recall information based on the VIN, it is a 2018 Kia which was subject to the Kia Engine Settlement (In re: Hyundai and Kia Engine Litigation , No. 8:17‑cv‑00838‑JLS‑JDE and Flaherty v. Hyundai Motor Company, et al. , No. 18‑cv‑02223 (C.D. Cal.)). Was never notified of such settlement as the VIN would have triggered this notification by Kia but they obviously did not list this in the recall.

Car would convulse and shake very wildly metal parts spread around engine. It has very rough idle. 4th cylinder went out and car only has about 99060 miles. The valve went out. My safety was very bad as car was not driving safely and shaking like a person having a seizeure each time it would stop. Vehicle has been inspected by a Kia dealer. This problem I had seems to get an issue many other people with Kia Optima have.

Trunk latch broke leaving it impossible for someone in the trunk to get out and very difficult for someone on the outside to open the trunk

On August 26, 2025, I brought my 2018 Kia Optima Plug-In Hybrid to an authorized dealer for recall SC218 (engine inspection and KSDS software update). The dealer verbally stated both SC218 and SC278 recalls were completed, and the repair order (RO #XXX) lists them as performed. In September 2025, Kia America emailed me showing recall SC218 still open, and a warranty coverage report dated September 26, 2025, again listed SC218 as unclosed. On November 4, 2025, NHTSA’s official VIN lookup confirmed the recall remains “Incomplete.” On October 21, 2025, Kia America emailed me under Case #XXX stating that SC218 was “confirmed completed” and that the dealer performed a software update to the ECU, referencing RO #XXX. However, NHTSA’s database still lists recall SC218 as incomplete. This contradiction between Kia America’s internal record, the dealer’s invoice, and the federal NHTSA database raises a serious safety concern that the recall inspection or software update was never actually performed or was never reported correctly. I have requested written proof and diagnostic data (Battery SOH report) multiple times but have not received them. If accurate, this means I was led to believe my vehicle’s engine-safety recall had been repaired when federal records still list it as open. I am requesting NHTSA to review this reporting discrepancy, ensure Kia America and the dealer produce verifiable proof of completion, and confirm that the federal record is corrected. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

My 2018 Kia Optima has a cracked oil pan, which caused an excessive oil leak —up to 5 quarts in a matter of hours. This eventually led to my engine going out.

Car suddenly stopped working; it was struggling to stay on. Mechanic stated cylinder is not functioning at full force.

My 2018 Kia Optima went into limp mode while exiting the freeway. I had it scanned and received a P1326 code, which is directly tied to the known engine knock sensor / bearing wear issue in Kia models. The engine light came on and the car lost power suddenly. This created a very unsafe situation. I contacted Kia, and they confirmed that my VIN is not included in the engine recall (KSDS campaign), even though my symptoms exactly match the covered vehicles. I am now stuck with an undriveable car and no recall coverage, even though I’m facing the same failure risk. I believe this VIN should be included, and that this is a clear safety issue. I am requesting the NHTSA to investigate and push Kia to expand coverage to include more affected vehicles.