2016 Kia Optima: engine overheating

Filed Aug 25, 2026 · Electrical, Lights · FL · crash

Vehicle was purchased in 2023. AC blower failure occurred for the first time in June 2024 and was repaired by PepBoys. On 4/2/2025 the ve3hicle had an active recall event when the engine seized on the highway because of a faulty oil pump/filter, Engine was replaced 4/17/2025 under that recall. Kia advised at the time that the wiring harness should be replaced due to electrical issues at the time but said that there was no recall for that work. At the time, there were no electrical failures of steering, brakes, all power etc. Nor did we know that those were a possibility. The wiring harness quote was $7,000, over the cost of the vehicle. It was decided to continue repairing the electrical issues as they came up, it was assumed that the fuses would blow before there because a safety or total vehicle failure, as automobiles are designed that way. 8/4/2026 the vehicle experienced a complete and total loss of power resulting in a traffic crash into another vehicle as the brakes felt like you were trying to push a wall rather than a pedal. There was minimal physical damage to the other car and the kia, the other driver got my husband's insurance information and then drove off. The car did startup after ~30 minutes or so and was driven home, but taken to the Kia dealership the next day. It was said that the blower motor overheated and melted a portion of the electrical junction box under the hood and that it was unsafe and dangerous to drive. Kia said that there were no active recalls for this work. the federal safety agency SC351 seems very similar to this issue that has plagued this car since the beginning. We would ask that Kia incorporate this vehicle and others outside of the year/model ranges in SC351 that have similar failure mechanisms as this seems common.

Filed Nov 19, 2025 · Engine, Fuel system · CO · fire

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 dealership (Fowler Kia of Windsor, CO) inspected the vehicle and quoted over $6,000 in repairs (melted engine wiring harness, ECM connector, battery cables, airbox, intake boot, etc.) while claiming the fire was “unknown cause/not the engine,” despite the clear knocking immediately preceding the fire. Kia Consumer Affairs has an open case but has not yet resolved coverage. This is a known, ongoing safety defect covered under multiple the federal safety agency investigations (PE21004, EA22002) and Kia recalls. I no longer feel safe in this vehicle and am requesting immediate investigation and inclusion in any expanded recall or remedy.

Filed May 15, 2025 · Engine · VA

The check engine light came on in the car. Upon having it checked at a local automotive shop, we discovered that the thermostat assembly is malfunctioning. This can cause the engine to overheat and shut off at any time which of course would be a severe danger. Additionally, a bad thermostat assembly in Kia vehicles can lead to engine overheating or overcooling, potentially causing engine damage and even a fire risk. Upon searching, this appears to be a common issue with the 2016 Kia Optima.

Filed Jun 12, 2024 · Engine · 102,175 miles · TX

The contact owns a 2016 Kia Optima. The contact stated while driving at an undisclosed speed, the contact became aware that the engine was overheating. Additionally, the contact stated that the vehicle failed to exceed 60 MPH, with the check engine warning light illuminated. The dealer was not contacted. The vehicle was not repaired. The manufacturer was not notified of the failure. The approximate failure mileage was 102,175.

Filed Jun 9, 2024 · Acceleration, Engine · AZ

Car was at about 70,000 upon purchase. Once driving it regularly, I immediately noticed a faint knocking noise upon acceleration. Also, when coasting the speed adjusted on its own intermittently, both up & down, not by much but enough that I felt it on the gas pedal. Other times it fails to accelerate when pushing on the gas pedal. I have to release the pedal & try again, sometimes more than once before it finally accelerates. Despite doing regular oil changes, my engine burns through oil long before next oil change is due, so I have to add 1 - 2 quarts of oil in-between changes. I was barely at 80,000 miles when engine started seizing & the following day the check engine light came on. It had to be towed to be serviced. They said the fuel injector or pump (not sure which) was allowing fuel to flood my engine which caused its damage. Even with what the warranty covered I had to pay $500 out of pocket so there were a lot of repairs. I can get a detailed print out of service if needed. When I do oil changes there's oil under the oil pan somehow, but its not leaking because there is no oil where I park. As of lately, even though all fluids are good, when the car is idle with a/c on, the temperature starts to go up until the car is in motion again, then the temperature goes back down quickly. It has only overheated once, which was the first time I noticed the problem because I was parked at a gas station on a hot day checking my phone & the a/c started blowing warm & dash said, "engine overheated". Only happen the one time because I have been cautious about watching the temperature to avoid it happening again. I recently passed emissions & had AutoZone do code reader check & nothing came back. In order to figure out problem I'd have to get diagnostics test that requires I leave the car for at least 2 days so it hasn't been something I can manage yet. My car is available for inspection if needed & I'm happy to provide detailed print out of repairs if requested.

Filed Oct 31, 2023 · Engine, Transmission · AZ

Vehicle Dash Check Engine Light came on 08/31/2023 Code P200A was found. Several weeks went by and vehicle started to hesitate pretty bad Vehicle was towed to Kia dealership on 10/04/2023 : Was told engine failure which needed replacement along with intake and several other required parts. Covered under Powertrain Warranty, vehicle was completed and ready for pick up on 10/17/2023 On 10/24/2023, on my way home from work, Dash Warning "Engine has overheated" has came on. Vehicle was towed back to original dealership. Kia reportedly found "air pocket" in cooling system. Vehicle was ready for pickup same day. On 10/30/2023, on my way to work, Dash Warning "Engine has overheated" has once again came on. Luckily I was able to get off the interstate and happened to be by a Kia dealership in the area. At this time, info is pending.

Filed Aug 11, 2022 · Fuel system · 47,000 miles · WA

The contact owns a 2016 Kia Optima. The contact stated that while driving at an undisclosed speed, the vehicle lost motive power with an unknown warning light illuminated. Additionally, the vehicle occasionally overheated while the coolant level was full. The dealer was made aware of the failure; however, the vehicle was not diagnosed nor repaired. The contact related the failure to a faulty low-pressure fuel pump. The manufacturer was made aware of the failure. The failure mileage was approximately 47,000.

Filed Jul 24, 2022 · Engine · IL

We purchased car used on 11/27/19. Within 3 days it was chugging, engine light started blinking, and we were broke down on side of the road. Federico Kia in Wood River IL had us tow car to service and told us then that there was an issue with these engines and they would be “replacing a part, and if it does this again, we would qualify for new engine. Would have been nice to know about issue with fires in engine prior to buying an 18000 car. After paying $400 for rental car they said it was fixed. Drove ok for another 9 months and then same thing happened yet this time we could smell something burning under hood. We were by dealership when this happened and due to it chugging and engine light, we took and dropped off again. We were then told spark plugs and needed oil change again after we had just changed ourselves 2 months prior. Said they were “flushing out engine” . Total cost was over $200 for us for oil change and flush. They said technically we were over our warranty time. SMH. It hasn’t been right since we bought it. We can’t afford to make their service dept rich, so we were told they would have to charge from them. We have had to replace same spark plugs 6 times as of today. We were just driving it after oil changes every 3 months even if miles driven were under 2000, and it’s chugging again and smoke and smell from under hood again. This engine is going to catch fire i fear. I won’t drive past 10 miles from my home because I have engine that chugs and overheats. Oil is not cheap and we put 2 qts in every 2 weeks or so. Dealership said there were no oil leaks they could see and yet puddle under car many times. Can someone please help us?

Filed Sep 2, 2021 · Engine · AZ

As I was driving on the highway my vehicle started to decelerate without warning. I was able to move to shoulder and when the car came to a stop the temperature gauge immediately went from cold to hot and the engine light came on and the dash displayed engine overheating. While researching what to do if your engine overheats, I came across the issues Kia has been having with their engines. I had the car towed to the dealership for inspection and was told my vehicle would not be covered because I didn’t do the product replacement which I had no knowledge of. After calling the manufacturer and talking to several reps I was ultimately blamed for the defect and not knowing about the problem so therefore it’s not Kia’s responsibility to fix my vehicle. One rep told me that Kia sent out notices according to DMV records, which means I should have received a notice. Another rep discovered that they did not have a correct address for me on file and said that it was my fault because I am supposed to update my address when I purchased the vehicle. I was also told by a supervisor that customers that buy new cars get priority in being contacted and that used car costumers are supposed to notify the manufacture when they buy a car so that’s why I received no notification of the recalls or product replacement. I received less than adequate customer service, and being blamed for a problem that resulted for Kias negligence is totally unacceptable.