2016 Kia Optima: adaptive cruise control problems

Filed Dec 16, 2025 · Engine · 70,000 miles · TX

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 federal safety agency hotline for further assistance. The manufacturer was not made aware of the failure. The approximate failure mileage was 70,000.

Filed Jul 13, 2025 · Acceleration, Electrical · OH

1) Rear passenger window failed a couple months ago. I believe it was regulator, not 100% sure. Cost me a couple hundred to fix. Now, few months later, the driver side rear window has failed. I rarely use the windows so I believe the failing parts are Kia known manufacturing defect. The dealer acknowledged that it’s a known problem with the vehicles like mine and even suggested the other one is going to fail soon. Now it has. If the dealership is aware then it’s likely a Kia flaw. If it’s a know manufacturing flaw, shouldn’t Kia should be fixing them instead of making customers spend upwards of $1k+ to fix both windows? 2) cruise control cuts off or doesn’t set and menus won’t go back to speedometer. While trying to set cruise control, it gets into the menu and won’t go back to the speedometer. Sometimes I have to pull over and stop to get the cruise control to work again. It gets stuck in the menu and can’t see the speedometer. Might get stuck on the trip screen, or the range. This has been happening since about 75k miles. It also doesn’t work with the pedal to set sometimes. Messing with it while driving can be a real hazard and sometimes I need to have cruise control to work. It’s deforming more than just inconvenient

Filed Jan 5, 2023 · Engine · MI

We purchased the car used (private party) in July. Afterward, we noticed it was using oil rapidly. We checked & refilled the oil several times. We also noticed a slight ticking sound when the car was running, but we did not think it was a problem. The day of the incident, the oil had been checked & topped off. Our college-age daughter was driving the car 70mph on I-75 north when she noticed a sound of high revving rpms while on cruise control. It continued to get louder over the next 2 minutes & became very concerning. She exited the freeway. The oil & engine lights came on at the beginning of the ramp. She was able to continue coasting through the light & into a parking lot, though the engine had limited power. Smoke filled the cabin & a strong smell, so she immediately exited the car. Smoke also came from the hood. The car could have caught on fire at this point, but we are glad it did not & our daughter's life was not harmed. We are thankful she exited the freeway when she did or she could have gotten into a wreck. These safety issues have occurred to some owners of this vehicle upon engine seizure. We had the car towed to Kia of Grand Blanc, MI. Upon inspection, they determined the engine had seized. They never opened the engine to look inside, only hooked up it for error code diagnostics. There was no record of the KSDS product improvement update being performed prior to the incident, so Kia Corporate has refused to replace the engine. Not the original owner of the car, we never received notification regarding this update. We had no way of knowing about it since we did not take it to a Kia dealership for maintenance (not required per the Magnussen-Moss Act (1975)). Prior maintenance was regularly completed at a local repair shop, & the previous owner provided us with all the records they had. The vehicle has not yet been inspected by anyone other than Kia. We are requesting an the federal safety agency inspection asap to pursue a covered engine and/or recall. Please contact us.

Filed Nov 10, 2022 · Engine · MN

My vehicle's engine stopped working on October 15th as my son was driving us 80 mph on I90 headed east just outside of Rochester MN. The cruise control was on but then the car started to decelerate on its own and he pulled onto the shoulder. It smelled like burnt oil. I opened the hood and saw nothing substantial; waited 5 minutes and tried to start it again and although it was turning over, it did not start. Check engine lights came on when the problem started and it vibrated violently twice. AAA took 3 hours to get us which was beyond stressful and scary watching in the rearview mirror as semis and cars in the right lane past us at 80 mph. The Luther Kia dealership in Inver Grove Heights MN stated eventually that the 2 cylinders have no compression and there is a broken exhaust valve. There is only 115K miles on it and I had it into the Bloomington Luther Dealership a month prior. Initially for the front collision sensor that wasn't working but when I pulled in, it smelled of burnt oil and the service tech and I discussed that I had notice it sputtering every once in a while when I accelerated from a dead stop. They said they fixed it by changing the gasket covers. Now Kia wants me to pay $9,000 for the engine to be repaired because my warranty doesn't cover it. I've researched and spoke to people and have heard comments have been made that these engines are constantly failing and they know about it. I would have never put my 15 year old son behind the wheel if I thought it was going to possibly die while we were going 80 mph.

Filed Jan 29, 2022 · Airbags, Driver assistance · GA

Suddenly, the warning lights on my dashboard resembled that of a christmas tree. I was seeing warning lights for the passenger airbag, blind spot warning/assist, auto-hold, adaptive cruise control, automatic emergency braking, lane departure warning, etc - were all suddenly offline. After finally getting an appointment scheduled with my local dealership, I was told that the airbag module had gone bad and needed replaced. With that module out, the car could not communicate with the other systems and thus was the cause of the errors/warning lights.

Filed Jun 7, 2020 · Acceleration, Electrical · 55,000 miles · MI

The driver door lock does not work. It is the only door that will not lock sometimes. Other times it is the only door that will not unlock. The cruise control does not always want to work. It will say cruise but will not let me set it.

Filed Dec 5, 2019 · Acceleration, Electrical · GA

Letter from congressman earl l buddy carter on behalf of constituent, regarding issues with a kia purchased in savannah, georgia. *ld the consumer stated the vehicle has experienced various issues including the battery being replaced 5 times in 8 months, multiple engine issues, electrical issues and a lack of acceleration. The consumer also stated, while driving with the cruise control activated, the vehicle would speed up to catch up to the designated speed and come in to close contact with the vehicle ahead. The failure is intermittent.

Filed Oct 5, 2018 · Acceleration · CA

2016 kia optima. Consumer writes with concerns malfunctions with advanced smart cruise control. *as

Filed Feb 5, 2018 · Acceleration, Transmission · 7 miles · WA

When the car encounters a hill and needs to downshift, either to climb or to hold back the speed when it descends, the cruise control remembers the downshift and will not return to high gear until a) it is manually overridden, but will still downshift up to 2 gears, when the lever is placed back to automatic or, b) when the cruise control is turned off. The cruise control also belatedly reacts to loss of speed control and overcorrects with too much power, resulting in a crude ride, as well. The workload is increased dealing with getting the car to attain top gear on flat roads, and is creating unsafe conditions, in my opinion. I have attempted to get this attended to at the dealership, and they continue to not fix the issue, as well as inform me I shouldn't be using cruise control on hills. My 2014 kia optima did not exhibit these issues, nor any other of my cars which had cruise control. There is a problem and these people will not fix it. The consumer stated the heat does enter the foot well area.

Filed Oct 31, 2017 · Acceleration, Engine · 2,000 miles · FL

I have been experiencing issues with my 2016 kia optima since I purchased it on september, 5th 2016. A short time after owning my new vehicle, first the car started to hesitate when starting as if it was struggling to start, the push button would turn red and the indicator lights would light up on the dashboard as if the key was not recognized in the car. The car would also self accelerate. On or around august 16th or 17th the car stalled out while it was being driven,we attempted to restart the car and it turned on like normal so the tow was canceled. , the service writer & kia all have copies of the videos the mechanic has also told me he was able to duplicate the issue, the solution was to change the fuel pump and service the fuel delivery system. Upon the services being completed we were contacted by the service manager, and kia that the car was ready to be picked up on september 6th 2017. While driving the vehicle home we noticed some hesitation while idle, also some strong acceleration when taking off from red-light or stop sign. While parked we noticed some strong vibration from the motor which the car had not had previously before service. Also after several attempts of starting the car, the car would either start rough, and also still had the same original occurrence as before with the key not being recognized in the car. With the car not fully starting and the push button turning red with the instrument panel lighting up with the key not in car light along with some others. On thursday september 7th, 2017 at about 4:30pm I had the cruise control set to 80 MPH, the car hesitated a couple times, then self decelerated to 73 MPH, reaccelerated to 82 MPH then self adjusted to 80 MPH, I contacted the dealership right after the occurrence I was told I had to wait to bring the car back in they had no loaner vehicles, not to use the cruise control feature.