Which parts fail
Components named in complaints (engine, cooling system, oil leaks, timing chain, exhaust).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2016 Kia Optima owners, lightly cleaned up (personal details are redacted by NHTSA).
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 contact owned a 2016 Kia Optima. The contact stated while coming to a stop, the vehicle leaned forward as if the engine had moved abnormally too far forward out of position. The contact stated that her boyfriend attempted to roll down the passenger's side window; however, the window failed to open as intended. No warning light was illuminated. In addition, the contact attempted to take the vehicle to the local independent dealer where it was purchased; however, the vehicle experienced a loss of automotive power. The vehicle was towed to the local independent mechanic, where it was diagnosed that the engine was blown and there was a hole in the engine. The contact was informed that the engine needed to be replaced. In addition, the contact diagnosed the failure and related the failure to the motor mount, alternator bracket, and in need of an intake manifold replacement. …
While driving, the vehicle suddenly developed a loud knocking noise from the engine. Within one block the vehicle began smoking heavily from under the hood. I pulled over, opened the hood, and flames were visible. This is a 2016 Kia Optima with the 2.4L Theta II engine. Approximately one year ago the original engine seized and was replaced by a Kia dealer under the Theta II engine recall (SC172/SC147) and class-action settlement. This is the second catastrophic failure of a Theta II engine in this vehicle. The replacement engine has now failed in the exact same manner as the thousands of other documented cases - rod bearing failure leading to knocking, overheating, and engine compartment fire. …
The contact owns a 2016 Kia Optima. The contact stated while driving 65 MPH, the check engine warning light illuminated and the vehicle stalled. The contact was able to veer to the side of the road. The contact was unable to restart the vehicle after several attempts. The contact also stated that she smelled an abnormal gasoline odor. The vehicle was taken to the dealer where it was diagnosed that an engine cylinder had failed. The dealer informed the contact that the vehicle could not repair under NHTSA Campaign Number: 18V907000 (Fuel System, Gasoline, Engine) unless the engine was knocking. The vehicle was not repaired. The contact stated that the engine was misfiring while driving and the vehicle would not exceed 40 MPH. The vehicle was taken back to the dealer where it was diagnosed that the engine was misfiring and oil was leaking onto the spark plugs. …
The contact owns a 2016 Kia Optima. The contact stated that while driving at 20 MPH, the oil warning light illuminated. The contact veered to the side of the road and checked the oil level of the vehicle with the assistance of her son. The contact stated that her son noticed that the vehicle did not have oil on the dipstick. The vehicle was taken to Pep Boys who had previously refilled the oil and the oil was refilled; however, the failure reoccurred while driving. The vehicle was taken to the dealer who diagnosed that no issues were found. The dealer advised the contact to bring the vehicle back after 1,000 miles. The dealer also advised the contact to not open the oil cap per the manufacturer's instructions. The contact stated that the failure had been reoccurring while driving. …
I have a 2016 Kia Optima FE and I keep up with regular oil changes and maintenance. My oil light has been flashing when I accelerate and when I turn, but turns off when idling. I've had this car 9 months and 2 weeks after getting it, that's the first time I've brought it to get serviced. I've always complained about the flashing red oil light when I'd get an oil change, but no one ever told me that my car was consuming oil until NOW. After they did the oil change, the car would be fine for about 900-1,000 and then it would come back on. I would always have about 3,000-4,000 miles left before I was due to get it serviced again. So, I would just get oil changes in between oil changes because that seemed to fix the problem. I went to the Kia dealership near me and they told me that my engine is consuming oil. He showed me the dipstick and it was bone-dry. …
The contact owns a 2016 Kia Optima. The contact stated that the vehicle was experiencing excessive oil consumption. The contact stated that she had been adding oil in the vehicle every 1,000 miles. The vehicle was taken to the dealer who performed an oil consumption test and diagnosed that the vehicle was burning an excessive amount of oil. The contact stated while driving 55 -65 MPH, the vehicle went into safe mode and decelerated to 25-35 MPH. The oil pressure warning light was illuminated. The accelerator pedal was depressed and the vehicle failed to respond and failed to exceed 35 MPH. The contact stated that the failure persisted. The check engine warning light was illuminated. Additionally, the contact stated that there was black smoke coming from the tail pipe. The vehicle was taken to the dealer where it was diagnosed that the engine needed to be replaced. …
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 contact owns a 2016 Kia Optima. The contact stated that while driving at approximately 70 MPH, the vehicle decelerated and went into LIMP Mode. The vehicle failed to go over 2,000 RPM. The vehicle was shaking and shuddering violently. There was a loud knocking sound detected at 1,500 RPM. There was an abnormal odor detected from the exhaust pipe. The check engine warning light was illuminated and flashing. The vehicle was taken to the local dealer, where it was diagnosed that the engine needed to be replaced. The engine was replaced on three occasions. The vehicle was repaired, but the failure recurred. The vehicle was taken back to the same dealer, who replaced the engine and catalytic converter. …
The contact owns a 2016 Kia Optima. The contact stated that the vehicle was consuming an excessive amount of engine oil. The contact stated that the oil level warning light was illuminated. The contact also stated that upon depression of the accelerator pedal, the vehicle would independently enter Limp Mode with the check engine warning light illuminated. The contact had the vehicle towed to Quirk Kia Manchester (1300 S Porter St, Manchester, NH 03103) where they initially updated the knock sensor. The contact stated that the failure persisted and the vehicle was towed back to the dealer where the knock sensor was replaced; however, the failure persisted. The contact then took the vehicle to KIA at Nashua (107 Daniel Webster Hwy, Nashua, NH 03060) where he was informed that engine oil had entered into the cylinder head and damaged the spark plugs. …
Related recalls
Engine
Kia Motors America (Kia) is recalling certain 2011-2017 Optima, 2012-2017 Sorento and 2011-2018 Sportage vehicles that previously received an engine replacement under recall number 17V-224, warranty, or the Knock Sensor Detection System (KSDS) Product Improvement Campaign.
Remedy: Kia has notified owners, and dealers will inspect and replace the fuel pipe, as necessary, free of charge. The recall began January 17, 2019. Owners may contact Kia customer service at 1-800-333-4542.
NHTSA investigations
Loss of Motive Power
The National Highway Traffic Safety Administration (NHTSA) received a letter dated July 13, 2022, petitioning the Agency to initiate a safety defect investigation into loss of motive power allegations attributed to oil drain pan assembly failures on certain Hyundai Motor America, Inc. and Kia America, Inc. vehicles spanning Model Years (MY) 2005-2021.
Engine complaints in other Optima years
Frequently asked questions
How common are engine problems on the 2016 Kia Optima?
NHTSA has 443 complaints about the engine & cooling of the 2016 Kia Optima, 58% of the model year's 759 complaints. The component named most often is engine › oil/lubrication (3 mentions).
Is there a recall for 2016 Kia Optima engine problems?
Yes — NHTSA recall 18V-907 (engine, Dec 19, 2018). Recall repairs are free at authorized dealers.
At what mileage do 2016 Kia Optima engine problems start?
Half of the complaints with a recorded mileage happened before about 91,000 miles, and 10% before 25,000 miles.
Is it dangerous?
Owners linked 4 crashes, 15 fires and 5 injuries to engine & cooling 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.