2016 KIA Optima engine problems

ENGINE

While driving at highway speeds on the freeway in San Diego, the engine of my 2016 Kia Optima catastrophically seized without warning. I instantly lost all power steering, brake assist, and electrical power, creating an immediate life-threatening emergency. The vehicle was towed to a Kia dealer. Corporate Techline and the dealership are refusing to perform the mandated settlement rod bearing test and are falsifying paperwork to deny the safety remedy.

NHTSA complaint #11758646 — an unverified report by a vehicle owner.

ENGINE

The engine assembly completely seized and the vehicle is currently stored at an independent repair shop . While traveling at high speed on Interstate 4 on July 24, 2026, the vehicle suffered a sudden, catastrophic loss of power and stalled in live traffic, creating an immediate threat of a high speed rear end collision. An independent service center officially confirmed the engine seizure after a dealership failed to perform an inspection during an eight hour wait, and no law enforcement or insurance inspections have occurred. Prior symptoms included severe, recurring oil loss requiring constant manual additions of oil between regular service intervals (most recently serviced in June 2026 at a kia dealership), and eventually the car completely shutoff on July24.

NHTSA complaint #11754979 — an unverified report by a vehicle owner.

ENGINE

engine failure, i was driving home from work and i went to accelerate from 0 to 20 miles and the car hesitated and didn't want to move. I took the car to the dealer three days later and it was confirmed that i needed a new engine. I was told by the dealership i was outside of my warranty but i just found out that i was covered up to 120k miles. No lights came on at the time and there wasn't any prior warnings to this happening. I had just put oil into the car two days earlier as i know in between oil changes that i have to put oil into the car and or check the oil to see if it is low.

NHTSA complaint #11753609 — an unverified report by a vehicle owner.

ENGINE

the engine. I was at a stop sign when the car stop responding to me pressing the accelerator and would not go. Upon further inspection it was noted that my car had no oil in it. I am diligent in getting my oil changed every 3 months or 3,000 miles. My engine had "seized" and i am being advised to purchase a new engine or purchase a new car. While trying to get my car to acclerate i was almost hit 4 times in a matter of 10 mins.

NHTSA complaint #11744474 — an unverified report by a vehicle owner.

ENGINE

My 2016 Kia Optima equipped with the 2.4L DOHC I4 GDI engine began to experience progressive and severe oil consumption during the latter part of my ownership. The oil warning light began activating repeatedly, even after shortly getting the oil changed. Several certified mechanics and oil change service stations told me this was an ongoing issue with this car and engine and that there was nothing I could do but monitor it and keep it filled. At their instruction, I monitored and had it changed more frequently, often topping it off at the oil change station and at home when needed. Approximately 2 weeks after an oil change upon putting the car in reverse it started to shake uncontrollably. The car was towed to a mechanic who stated I needed an engine. I then towed it to an authorized Kia franchise dealership where the technician documented the oil consumption complaint, confirmed a Cylinder 2 misfire code, performed a borescope inspection, and found the Cylinder 2 exhaust valve burnt with a chunk missing. Engine replacement was recommended by the Kia dealership technician. Prior to my purchase, the engine had already been replaced at approximately 80,000 miles under recall-related circumstances. The replacement engine installed by a Kia dealership subsequently failed, exhibiting symptoms consistent with the documented widespread defect affecting the 2.4L DOHC I4 GDI engine in 2016 Kia Optima vehicles, including severe oil consumption, cylinder misfire, and catastrophic internal engine damage confirmed via borescope at a Kia franchise dealership. Kia America denied the claim based solely on mileage despite the damage being confirmed by their franchise technician. My vehicle became unsafe to drive due to this engine instability shortly after starting before becoming fully inoperable. My vehicle has been non-operational for approximately 5 months. Kia has not provided a substantive written determination despite a formal written demand submitted in March 2026.

NHTSA complaint #11744531 — an unverified report by a vehicle owner.

ENGINE

The car returned P1326 and had multiple misfires and audible knocking, the dealers will indeed fight the already existing class action warranties. Was sent home and told to “drive the fuck out of it”, to which the car did not make it home and blew gasoline into my cabin while driving on the highway. Almost passed out, and am still fighting Kia to actually address the defective rod bearings. I personally would fight tooth and nail over a 5 dollar problem, but this is something they do nationwide and can cause serious injury or death. If it weren’t a 200 LB man driving the gasoline shooting into the cabin would absolutely cause a knockout. To the time of this report they are still trying to disregard the rod bearing issue and send me home with fixes to problems caused consequentially.

NHTSA complaint #11742694 — an unverified report by a vehicle owner.

ENGINE

The contact owned a 2016 KIA OPTIMA. The contact stated that while driving at 30 MPH occupied with her husband the contact heard a noise coming from the rear of the vehicle and smoke coming from the rear of the vehicle as you looked in the drive side rear view mirror and while depressing the brake pedal attempting to come to a complete at the traffic light, the brakes failed to work a intended. No warning light illuminated. The contact mention she kept trying to depress the brake pedal, however the vehicle kept accelerating causing the vehicle to crash into a ditch, go around a telephone poll, crashing into a rock garden which allowing the vehicle to come to a complete stop. The vehicle was towed to a towing lot call interstate towing then the vehicle was then towed by insurance company to a collision center. No injuries were sustained. No medical attention. The fire department extinguished the fire. The contact stated a police report was filed. The vehicle was destroyed. The manufacturer was not made aware of the failure. The approximate failure mileage was 166,834.

NHTSA complaint #11741833 — an unverified report by a vehicle owner.

ENGINE

The Kia had a problem with the check engine light coming on and it gently went into limp mode. I had it repaired at Darlings Ford and it worked for about 600 miles. I had it repaired again and it worked for about 7,000 miles. The light recent came on and the car immediately hard banged andwent into limp mode. My wife was driving and shaking when she got home. The light went out and everything was fine. A couple of days later, on 5/27/26, we were on the interstate in traffic travelling 70 mph and it Violently hard bumped, the Cel came on and it went into limp mode. It was as if we hit deep pot holes with both front tires which we didn't as we were on a smooth highway. The light is still on and it's in limp mode.

NHTSA complaint #11740798 — an unverified report by a vehicle owner.

ENGINE

This vehicle is eligible for Theta II class action settlement, and I cannot seem to get the Kia dealerships, or the Kia Corporate to honor the engine failure issue that I was told by the AAA mechanic should have been replaced. I have also been told by others, including another mechanic at a nationally recognized mechanic that it needs to be taken care of, and that they had the same vehicle and had there's taken care of without any issues.

NHTSA complaint #11740644 — an unverified report by a vehicle owner.

ENGINE

While accelerating onto the highway in my 2016 Kia Optima 2.4L, the vehicle suddenly lost all engine power without warning. The vehicle would no longer accelerate and I was forced to coast and brake to safety. Immediately after the engine shut off, the check engine light, oil light, and battery light illuminated on the dashboard. After the incident, the vehicle would not restart or crank at all. The electrical systems, dashboard lights, and chimes still function normally, and the battery is new. The vehicle had proper oil level at the time of failure. No warning signs were present prior to the sudden loss of power. This failure created a serious safety hazard because it occurred during highway acceleration and left the vehicle unable to maintain speed or move out of traffic safely. Based on the symptoms and sudden engine shutdown, I am concerned this may be related to the known Theta II engine issues associated with Kia Optima vehicles.

NHTSA complaint #11739772 — an unverified report by a vehicle owner.

ENGINE AND ENGINE COOLING

The contact owns a 2016 Kia Optima. The contact stated that while operating the vehicle a knocking and rattling noise coming from the engine and the check engine light had remained illuminated. The vehicle was towed to the local dealer who informed that the engine had failed and needed to be replaced. The vehicle was not yet repaired. The manufacturer was notified of the failure but no assistance was offered. The failure mileage was 150,000.

NHTSA complaint #11739444 — an unverified report by a vehicle owner.

ENGINE

Issue 1: High oil consumption in the engine due to poor engine design, according to the auto repair center. 5 quarts of oil are added to the engine once every 2-3 weeks. All oil leaks were previously repaired, but oil is still burning off. Issue 2: The engine has misfired more than once, with a puff of smoke coming out of the exhaust. Issue 3: Twice in the past 1.5-2 years, multiple spark plugs have failed, causing a breakdown. This is a Theta II engine, but it is not in the class action settlement.

NHTSA complaint #11738122 — an unverified report by a vehicle owner.

ENGINE

I purchased a Kia Optima 2016, in December of 2025. At the time the car wouldn't go over 60 mph. I hauled the car to Kia to have it inspected. The Kia dealership informed me that there is a recall on that particular car for an engine replacement. They tested the car and later informed me that they believed I purchased the car knowing it had a recall and wanted the engine replaced for free so I could sell the car. The car is not for sale, and I had/have no intentions on selling the car. I went ahead and paid $6100 for the engine to be replaced. I later did research and learned that if a car has a recall, it doesn't matter my intentions with the car. I felt that Kia denied a replacement engine because of their opinion of me and not for the recall. The car is registered and insured in my name and is being driven daily. At this time, I feel that I deserve a refund of the $6100. Can you guide me on which steps to take on this matter?

NHTSA complaint #11736596 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2016 Kia Optima. The contact stated that while driving 70 MPH, the check engine warning light illuminated. An independent mechanic was contacted. The vehicle was taken to an independent mechanic to be diagnosed. The contact was made aware of a misfire coming from the engine. The vehicle was not repaired. The manufacturer was notified of the failure but offered no assistance. The approximate failure mileage was 160,000.

NHTSA complaint #11732716 — an unverified report by a vehicle owner.

ENGINE

FOR THE PAST 3 YEARS, IVE BEEN HAVING PROBLEMS RELATING TO MY ENGINE BURNING OIL TO FAST, ENGINE SHAKING AND NOT ACCELERATING LIKE ITS SPPOSE TO... YOU HAVE A RECALL ON 2016 OPTIMAS BUT ONLY THE HYBRID (HEV). WHICH WE ALL KNOW ITS NOT RIGHT. WHY ONLY DO IT FOR CERTAIN OPTIMAS KNOWING WE ARE ALL (ALL OPTIMAS) ARE GOING THROUGH THE SAME THING!! SPENT THOUSANDS OF DOLLARS, IN AND OUT OF DEALERSHIPS AND AUTO SHOPS AND NOW IM MENTALLY DRAINED , UPSET, CONFUSED AND OVERALL FEEL MANIPULATED BY KIA... NICE CARS BUT DOES NOT KEEP ITS VALUE.. CAN SOMEONE FIX THIS PROBLEM

NHTSA complaint #11731203 — an unverified report by a vehicle owner.

ENGINE

Car is not holding oil it acts like it's gonna cut off while driving and it jerking was diagnosed with colitic converter p0604

NHTSA complaint #11727436 — an unverified report by a vehicle owner.

ENGINE

I purchased a vehicle from Banter Auto here in Wichita, Kansas. I reviewed the Carfax beforehand and nothing stood out that scared me so I signed off and purchased the vehicle. I have had nothing but problems since buying which was 7 months ago and have spent $9000 on repairs. I’ve been told by several mechanics the last 5 times I’ve been in and out of mechanic shops it’s evident my car sat in deep water for a long period of time. I finally took it to an electrical auto specialist here in town and while he said it is evident my vehicle sat deep water for a period of time and while the corrosion hasn’t quite started to cause an electrical problem that it very well could down the road. I’ve given the man who owns the dealership and opportunity to make this right however he stopped responding. I believe that is illegal and I’ve been told it should’ve been a “flood title”. I will know for sure after seeing a I will know for sure after seeing an attorney this week. That was not disclosed to me or I would definitely would have not purchased the car. When I first got the car, the locks and windows were going insane flickering all over the place and Kia dealership told me it was quite crazy and nothing they had seen before, however, they were able to fix it. I strongly believe that when my car was flooded it caused something to happen that I’m only going to have to keep paying for overtime. I’m already in debt from the $9000 I’ve had to getting personal loans. This is causing me enormous emotional distress. Please help.

NHTSA complaint #11723539 — an unverified report by a vehicle owner.

ENGINE

These cars have a known issue for burning oil the motor thats in my car was recalled for same issue but they are not trying fix my car under that recall of the bad motor that they did recall

NHTSA complaint #11723153 — an unverified report by a vehicle owner.

ENGINE

2016 Kia Optima engine locked up, vehicle stalled on interstate,heard a rod bearing sound, left me in limp mode trying to get out the way of 18 wheelers traveling behind me. Towed into Kia dealership which confirmed the engine locked up which has a recall #PI1802B KSDS, but denied to cover it because I didn't have this recall done. I also called Kia Customer Service, they denied me too and just gave me a case #[XXX]. I explained to them that I never received notice of this recall. So how could I prepare for something like this to happen while traveling from Texas to Louisiana to visit my grand kids. The dealership gave me a Quote of $9735 for parts and labor, which I don't have, I am still making payments on this vehicle. Now I am stuck in Louisiana with my vehicle, also it's going to cost me even more to have it towed back to Texas. Please help me understand why the dealership won't stand behind a safety recall or what one person I spoke with called a campaign recall, which ever! That I never received notice about this recall. I hope the "President" or the "President of the Company" will step up and help, after all we as Citizens don't have a problem spending our hard working money on purchasing these vehicles from the dealerships, to have things like this to happen out of our control. Thanks for at least Listening. GOD BLESS...INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA complaint #11722291 — an unverified report by a vehicle owner.

ENGINE

Engine oil light doesn’t work. Oil light flashed a couple of times in separate instances. Checking oil dip stick which smells like burning oil and dip stick hardly showed any oil left.

NHTSA complaint #11721839 — an unverified report by a vehicle owner.

ENGINE

engine light start blinking out of no where and speed started to reduce while on the highway. my fix finder gave me code P1326

NHTSA complaint #11719661 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2016 Kia Optima. The contact stated that while driving at 60 MPH, the vehicle stalled with the check engine light illuminated. The brake pedal was depressed, and the steering wheel seized. The contact was able to pull over to the side of the highway and contacted the Highway Patrol for assistance. The contact associated NHTSA Campaign Number: 18V907000 (FUEL SYSTEM, GASOLINE, ENGINE); with the failure; however, the VIN was not included in the recall. The vehicle was towed to the residence. The dealer was not notified. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was 105,000.

NHTSA complaint #11718486 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2016 Kia Optima. The contact stated that while driving at an undisclosed speed, the vehicle shuddered. No warning lights were illuminated. The vehicle was taken to a dealer, where it was diagnosed and determined that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure and stated that the knock sensor needed to be installed prior to the failure for the engine replacement to be covered under warranty. The failure mileage was approximately 143,000.

NHTSA complaint #11718631 — an unverified report by a vehicle owner.

ENGINE

My vehicle’s engine was previously approved for replacement under the lifetime engine warranty associated with the settlement, confirming that my vehicle falls within the covered class. However, I am now experiencing significant difficulty obtaining assistance regarding secondary damage that directly resulted from the engine failure, specifically the failure of the starter and related operability issues. Despite multiple attempts to resolve this matter through the dealership and warranty channels, I have been repeatedly redirected without meaningful assistance or clear resolution. I have also encountered discrepancies within the online settlement VIN verification tool, which appears inconsistent with Kia’s prior acknowledgment of my vehicle’s settlement-related coverage.

NHTSA complaint #11716972 — an unverified report by a vehicle owner.

ENGINE

The engine stalled without warning while I was pulling out of my driveway into the street, creating an unsafe condition due to sudden loss of power. After waiting briefly, the vehicle restarted and was moved back into the driveway. It was towed the following day due to loss of confidence in safe operation. The vehicle was diagnosed with engine failure consistent with known defects affecting Kia Optima vehicles equipped with Theta II engines. Kia denied coverage under the extended engine warranty / class action settlement solely because the KSDS (PI1802 ECU update) had not been installed prior to the failure. As the second owner, I was never notified of this update before the incident and had no opportunity to complete it. This failure was sudden, unanticipated, and safety-related. I am submitting this complaint to document an engine stall and loss of power condition posing a safety risk.

NHTSA complaint #11715316 — an unverified report by a vehicle owner.

ENGINE

The engine is a problem and all I’m ever told us “ this vehicle is know to have engine problems. This is dangerous to have in the road. Kia is aware of this. Why sale the vehicle knowing this and not disclosing this info to the consumer upon purchase. There is no truth in lending. It’s plain sight robbery. What if I’m far from home and stranded because vehicle set fire or broke down in hazardous condition weather. I constantly needing oil changes because of this engine. The dealership is aware. They tell me to trade it in or get rid of it because it’s going to go for a fact. I’ve never missed oil changes. I put oil every time the oil indicator light comes on. Now for the 3rd time the check engine light is on. 2 times for misfire code. The vehicle engine holds sludge no matter how much you get oil changes. The mechanic told me this year make and model is known for this very fact. I want my money back. Kelly blue book don’t give enough. I was scammed into this car but I managed to pay it off. A car the sales person scammed me and wouldn’t take the vehicle back. I complained to the general manager. They always act like he wasn’t available. They kept claiming new ones started. After almost a year of those games I had to move and the case never got solved. But even when I complained their maintenance person stole my rims. They told me prove it. Just all bad experience. I just want my money. Even if they gave me another engine. It’s still going to be the same problem. A bad engine. 2016 Kia optima’s should not have been continuously sold with them knowing it has bad engines. Even the headlights don’t work. Very dim. Car smells like burning fumes when driving. Please please help. This isn’t fair lending practice. People trust them and they are dishonest sellers.

NHTSA complaint #11714744 — an unverified report by a vehicle owner.

ENGINE

My 2016 Kia Optima experienced a sudden catastrophic engine failure in July 2025. The failure is consistent with widely reported Theta II engine rod bearing defects that cause engine seizure and stalling. The vehicle did not receive the Knock Sensor Detection System (KSDS) update prior to my ownership, and I was never notified of this critical safety-related update. The engine failure occurred without warning and could have resulted in loss of power while driving, creating a serious safety risk. This vehicle model year has a documented history of engine defects and class action settlements related to premature engine failure. I believe this represents an ongoing safety defect. I am requesting that NHTSA review this failure as part of its investigation into Kia Optima engine defects.

NHTSA complaint #11714650 — an unverified report by a vehicle owner.

ENGINE

While driving my 2016 Kia Optima, the vehicle experienced a sudden and complete loss of engine power and stalled without warning. At the time, I was Door Dashing for income. The engine seized and the vehicle came to an immediate stop in the middle of 4925 Wolf Creek Dr SW, Atlanta, GA, a narrow two-lane road with limited street lighting. I was forced to remain stopped in the roadway in darkness for over an hour while multiple oncoming vehicles passed by, creating a serious safety risk. The vehicle could not be restarted and had to be left on the roadside overnight. The following day, the vehicle would only start briefly when jump-started, ran for approximately 15 seconds, and shut off again. It could not move and was towed to an authorized Kia dealership. At the dealership, technicians jump-started the vehicle, performed diagnostics, added engine oil, cleared codes, reset adaptive values, and conducted a test drive. During that test drive, the engine seized again, and the vehicle had to be towed back. Kia approved a full engine replacement under its extended engine warranty, acknowledging engine failure consistent with known defects. However, after the engine replacement, the vehicle would not start at all. Kia stated oil intrusion from the failed engine damaged electronic components, leaving the vehicle non-operational. Kia denied coverage for the resulting damage and issued an estimated $6,000 repair bill for engine harness, injector sub-harness, and ECU replacement. The vehicle remains inoperable following an approved warranty repair. This incident involved sudden loss of propulsion while driving, occurred without warning, resulted in repeated engine seizure, and left the vehicle disabled in traffic at night. This appears consistent with known Kia engine defects and presents a serious safety concern that warrants investigation.

NHTSA complaint #11711035 — an unverified report by a vehicle owner.

ENGINE

Car is burning a lot of oil, took to dealer went through several tests and they claim burning 1.5 quarts was within limit for 1000 miles. Then started getting misfire codes and car went into limp mode a couple of times. They said to replace spark plugs because they were fouled and clean injection. Performed those requested actions, then 45k later getting misfire codes again, took to another dealer they said plugs are fould and clean injection again. Asked them to provide a permanent fix for the issue so the car does not keep fouling out the plugs and they said the only way to fix was to replace the motor. I asked, since you have no guaranteed fix why don't you replace the defective motor under warranty. They said because it is not locked up or throwing a specific code detecting a knock in the motor. So I said the motor will have to completely fail before a replacement would be approved they said yes (basically suggesting I somehow blow up the motor). This is wrong, a product under warranty from manufaturer and cannot be fixed without replacing the part should be covered. I do not know what my options are at this point, the milage warranty has run out and they will not do anything to fix it, just bandaids until it dies. the dealers would not put it in writing only verbally telling me.

NHTSA complaint #11709938 — an unverified report by a vehicle owner.

ENGINE

Engine brocked the pistones brock stock engine and pay for new engine

NHTSA complaint #11707061 — an unverified report by a vehicle owner.