2016 Kia Optima Engine
Owner-reported problems and safety issues filed with NHTSA. Review common failures, severity levels, and complaint trends over time.
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Chronological view of owner reports
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.
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.
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.
engine light start blinking out of no where and speed started to reduce while on the highway. my fix finder gave me code P1326
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.
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.
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.
Engine brocked the pistones brock stock engine and pay for new engine
The contact owns a 2016 Kia Optima. The contact stated that while driving approximately 40 MPH, a knocking sound coming from the engine compartment was heard, and the check engine warning light illuminated. The contact further stated that while driving at approximately 80 MPH, with the cruise control mode engaged, the vehicle started to stall and failed to exceed 30 MPH. The contact stated that the cruise control became inoperable, and the check engine warning was flashing. The vehicle was restarted; however, the vehicle continued to hesitate and failed to exceed 30 MPH while driving. The dealer was contacted, but the vehicle was not diagnosed or repaired. The contact was referred to the NHTSA hotline for further assistance. The manufacturer was not made aware of the failure. The approximate failure mileage was 70,000.
The engine lost cylinder 3, piston came loose and broke the spark plug. This happened because the rod bearing came loose which has been a known issue with Kia. There’s already been a class action law suit, and recall with warranty. Now the Kia dealership in Lynchburg has refused to honor this warranty. Stating they can’t do the required rod bearing clearance test because the engine doesn’t have compression. The engine has no compression because the rod bearings came loose and shoved the piston into the head.
The contact owns a 2016 Kia Optima. The contact stated that while driving at various speeds, the vehicle suddenly stalled. After restarting the vehicle, the vehicle operated normally. The contact stated that the failure had occurred on several occasions. The cause of the failure was not yet determined. The local dealer was notified of the failure, but no assistance was provided. The manufacturer was not notified of the failure. The failure mileage was 100,000.
My engine blew up and started smoking while driving
My 2016 Kia Optima EX (VIN [XXX] , 2.4L I4 DI) suffered sudden engine bearing failure and complete engine seizure after approximately three months of use. After inspection, the Kia Scottsdale dealership confirmed that my vehicle’s VIN was eligible under the engine replacement warranty and submitted a request for assistance.However, Kia America denied the request. This defect is identical in nature to the known dangerous defect covered under Kia Safety Recall SC147 (NHTSA 17V-224) and related recalls for earlier Optima model years, involving connecting rod bearing wear leading to engine seizure. In my case, the defect caused a total loss of motive power, posing a serious crash risk. Kia Motors America has refused to repair or replace the engine, claiming my vehicle is ineligible due to being purchased from an auto auction (Sierra Auction) and having multiple prior owners. This refusal ignores that the defect is a safety-related manufacturing flaw identical to those already acknowledged by Kia and subject to federal recalls. I request NHTSA investigate Kia’s refusal to extend the same safety remedies to my VIN and consider whether the scope of SC147 and related recalls should be expanded to include vehicles with the same defect pattern. Supporting documentation available upon request. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
The contact owns a 2016 Kia Optima. The contact stated that while driving at 45 MPH, there was a misfire coming from the engine, and the vehicle was shaking. There was no warning light illuminated. The vehicle was taken to an independent mechanic to be diagnosed. The vehicle was diagnosed with engine failure due to piston rings failure, causing coolant intrusion into the engine. The contact was informed that the engine needed to be replaced. The contact stated that the ignition coil, cylinder #1, and spark plugs were replaced. The dealer was contacted, but had not diagnosed or repaired the vehicle. The manufacturer was not made aware of the failure. The failure mileage was approximately 100,000.
The contact owns a 2016 Kia Optima. The contact stated that while driving at approximately 55 MPH, the vehicle lost automotive power. The check engine and the engine oil warning lights were illuminated. The vehicle was towed to a local independent mechanic where it was diagnosed and determined that the engine needed to be replaced. The local dealer was contacted; however, the vehicle was not repaired. The contact stated that the vehicle warranty had expired. The manufacturer was made aware of the failure. The failure mileage was approximately 147,000.
My 2016 Kia Optima is experiencing severe internal engine oil consumption that matches known issues Kia has recalled and extended warranties for. The vehicle loses 1–3 quarts of oil every few days with no external leaks. A repair shop found a P0304 cylinder 4 misfire, P0010 cam actuator code, and spark plug damage caused by oil entering the combustion chamber. They confirmed internal engine damage and abnormal oil consumption. The Kia dealership refused to assist due to mileage, even though this issue matches the engine defects covered under Kia’s litigation settlement and warranty extensions. The excessive oil consumption creates a dangerous safety risk, including engine stalling, loss of power, and potential engine seizure while driving. I am requesting NHTSA review because the vehicle’s condition is unsafe and part of a widespread engine defect.
Engine Is knocking that happened when I took my car 3 times to emission test and my car didn't pass after that I took it to my mechanic for the diagnostic and he told me you have to take it to kia dealer but I was shocked the way how they treated me and they completely refuse to replace my engine they came up with too many excuses and I have recall repair active I have right to fix my car but they didn't with bad attitude
Engine began jumping during driving and loss power. No dashboard illumination warning lights and the temperature gage showed normal operating temperature. Car was not accelerating properly. Had to maneuver carefully to prevent being ran over. Engine light illuminated showing misfire. Replaced ignition coil pack and spark plugs. Driving again, car stalled. No dashboard warning lights. No high temperature on gauge. Narrowly missed being hit by a semi as there was absolutely no warning and we were on an Interstate bypass ramp with nowhere to pull over!! Towed car to dealership for diagnosis. Results: engine blown, turbos gone, and the catalytic converter is holding oil. Dealer is stating this is not covered under the extended warranty from Kia as its not connector rod bearing issues and that the piston rings failed. However, they stated the turbos got "too hot" and they failed. The gauges have never shown that the car was running hot. I have a sworn statement from my mechanic stating this is absurd and a valiant attempt to not pay for what would be the second warranty replacement of my engine. The piston rings failed as a result of the connector rod bearing failure. The "too hot" temperature that damaged the turbos was likely caused by the same bearing issue. The heat from the bearings unseated the piston rings and allowed the engine to dump its oil causing the engine to fail. I highly recommend that you open an investigation into these issues. The car not accelerating and losing power at interstate speeds is a very serious and dangerous issue.
The contact owns a 2016 Kia Optima. The contact stated that while driving approximately 75 MPH and attempting to accelerate to overtake a semi-truck, the vehicle suddenly started losing automotive power and then stalled. The vehicle was towed to the local dealer, who diagnosed that the engine had seized and needed to be replaced. The vehicle was not yet repaired. The contact indicated that prior to the failure, the check engine warning light illuminated and remained illuminated, and the engine experienced excessive oil consumption. The manufacturer was not yet notified of the failure. The failure mileage was 45,000. The VIN was not available.
The engine is starting to fail causing issues such as being able to accelerate. When driving on the freeway it caused a safety issue it began slowing down on the interstate. The vehicle has been inspected by mechanics. No warnings prior to problem. They appeared day before due for an oil change. The car also burns oil really fast sometimes causing car to smoke. I have a GDI turbo engine and have been told that the engine i have has been recalled a few times on different models cars.
No FireNo Injuries0 Deaths0 I’m experiencing severe oil consumption and spark plug fouling, which are known problems with the GDI engine. This is affecting driveability and may indicate piston ring or valve seal failure. My engine code starts with G4KJ which falls under the current recall, but my vin does not show up. Why isn't my car eligible? I have called Kia and their response was to call my local dealership. Started noticing the issue on [XXX]. Called dealership at that time and they said my car doesn't qualify. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
I’m experiencing severe oil consumption and spark plug fouling, which are known problems with the GDI engine. This is affecting driveability and may indicate piston ring or valve seal failure.
Engine issue, it’s knocking loud and misfires. Engine light flashing and Car went into limp mode , will not go over 60 mph . I have changed the spark plugs, knock sensor, and had an oil change nothing has fixed my issue.
The contact owned a 2016 Kia Optima. The contact stated while driving at an undisclosed speed, the contact noticed smoke coming from under the hood. The contact stated that the passenger, who was seated in the rear passenger's seat, advised the contact to stop the vehicle. The contact stopped and parked the vehicle. The contact and the passenger exited the vehicle. The contact stated the engine was on fire. The Fire department arrived and extinguished the fire. A Fire report was filed. No police report was filed. No injuries were sustained. The vehicle was towed to a local tow yard. The vehicle was condemned as a total loss. In addition, the contact stated that two days before the failure, the vehicle was serviced by an independent mechanic. The independent mechanic replaced the engine sensor and the valve cover gasket. The manufacturer was made aware of the failure and a case was filed. The failure mileage was approximately 66,000.
The vehicle went into limp power mode while driving
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The 2016 Kia Optima has 279 Engine complaints on file. 1 crashes have been reported. Review the timeline above for detailed owner experiences.