2025 Kia K4 engine problems

Filed Nov 4, 2026 · Electrical, Engine · GA

Vehicle Safety Complaint – 2025 Kia K4 Unexpected Engine Shutdown I own a 2025 Kia K4 purchased new in August 2025. I am reporting a serious and recurring safety concern involving unexpected engine shutdown while the vehicle is being operated. The vehicle has experienced intermittent engine shutdowns, including while traveling at highway speeds. During these incidents, the vehicle switches into Accessory Mode, resulting in an unexpected loss of engine power while in motion. This issue first began before the vehicle reached 24,000 miles. The vehicle currently has approximately 58,000 miles. I previously brought the vehicle to an authorized Kia dealership for diagnostic evaluation. However, the dealership was unable to reproduce the problem or identify its cause. The underlying safety concern remains unresolved. I am particularly concerned because an unexpected engine shutdown at highway speeds creates a significant risk of a collision and endangers the occupants of the vehicle and surrounding motorists. I have also become aware of other owner-reported incidents involving 2025 Kia K4 vehicles experiencing unexpected shutdowns and switching into Accessory Mode while driving. I am requesting that the federal safety agency document this complaint and evaluate whether this recurring condition represents a potential safety-related defect affecting 2025 Kia K4 vehicles. I am willing to provide additional documentation, dealership records, and vehicle information if needed. Vehicle: 2025 Kia K4 Purchase date: August 2025 Current mileage: Approximately 58,000 First occurrence: Before 24,000 miles Dealer investigation: Conducted, but no cause identified.

Filed Jul 7, 2026 · Engine · 69,085 miles · OH

The contact owns a 2025 Kia K4. The contact stated while driving at 40 MPH on several occasions, the vehicle stalled. The vehicle was able to restart but would immediately stall again, requiring the driver to wait approximately 10 minutes before the vehicle could be successfully restarted and driven. The vehicle was towed on one occasion and taken to the same dealer twice, but the dealer was unable to replicate the failure. The manufacturer was notified of the failure. The failure mileage was approximately 69,085.

Filed Jul 4, 2026 · Electrical, Engine · NC

The car completely cut off while driving on the highway going 65 mph. This isn’t the first time it has turned off while driving. I had to pull over and put the car in park before it would turn back on. The error says Accessory Mode. I have taken the vehicle to Kia Dealership in Winston Salem but they told me they are unable to recreate the issue so they are unable to assist with the problem. The car turning off while driving has happened at least 20 times. I have repeatedly called Kia and they are unwilling to diagnose an issue with the vehicle unless it happens while they have it. I am putting myself and others at danger driving this vehicle. I contacted Hertz Auto sales where I purchased it and they directed me to contact Kia since I have a warranty. I plan on taking the car again but I can only hope the issue happens while they have it because this vehicle is VERY dangerous to be on the road and I have no other option than to be at the dealerships mercy.

Filed Jun 22, 2026 · Body, Engine · CA

“The engine undercover (belly pan) detached and is dragging/scraping on the ground on a 2025 Kia K4 with approximately one year of normal use. The radiator support is also affected. Dealer (Selma Kia, Selma CA) denied warranty coverage and stated damage was caused by driver hitting a speed bump. These are factory-installed components on a one-year-old vehicle and should not detach under normal driving conditions. This appears to be a fitment or installation defect.”

Filed Jun 12, 2026 · Driver assistance, Electrical · 58,000 miles · FL

The contact owns a 2025 Kia K4. The contact stated that while driving at 75 MPH, the vehicle downshifted upon depression of the accelerator pedal, with heavy white smoke coming out of the exhaust pipe. The contact stated that the low oil pressure warning light was illuminated prior to the failure. The contact pulled off the highway and drove into a store parking lot as the engine made an abnormal knocking sound. The contact requested assistance from a bystander, who advised the contact that the head gasket appeared to have blown. The contact checked and noticed that the coolant and oil levels were low. The contact added both oil and water to the vehicle and drove to the residence. The contact made a diagnosis appointment with a local dealer. Upon starting the vehicle, the check engine warning light illuminated, and the contact decided to tow the vehicle to the dealer. The dealer determined that the engine needed to be replaced due to sludge. Additionally, the contact stated that the vehicle had experienced various electrical failures, as the trunk, power door, and power windows buttons were inoperable. The contact also stated that the rearview camera image remained displayed while in drive(D) for an extended period. The contact was provided an estimate for the repair, and the vehicle remained in the dealer's possession. The manufacturer was notified of the failure and provided a case number. The vehicle was not repaired. The failure mileage was approximately 58,000.

Filed Apr 6, 2026 · Engine, Transmission · FL

As I entered onto i4 reaching the speed of 60 miles an hour my vehicle began to make a high pitched whining noise that got louder as I pressed on the gas pedal, noise dissipated when I let off the gas pedal. Vehicle began to slow down on its own , even when applying pressure to the gas pedal, I had no choice but to pull over on i4, error message displayed “RED CAUTION EMBLEM” error message “Transmission Control Unit” Kia k4 app displayed Diagnostic Alert AT PO72200

Filed Feb 19, 2026 · Engine, Transmission · NJ

Engine Failure, Engine cooling and lost power

Filed Sep 8, 2025 · Engine, Transmission · FL

Sluggish acceleration, after I got an oil change a few weeks ago. No warning lights whatsoever, I’m thinking it’s the transmission , taking awhile to speed up especially on highway

Filed Aug 29, 2025 · Acceleration, Electrical · NJ

Transmission failure 4 times since purchasing it new in December 2024 I was almost killed multiple times on the highway because car won’t accelerate. Car is jumping when driving and choking Air conditioning shuts off while driving Car gets stuck in park and nothing will work

Filed Jun 18, 2025 · Engine, Fuel system · CA

Bought my Kia k4 2025 in February at DTLA Kia and the experience has been [XXX]. The first day driving I went up near dodgers stadium , immediately had a burnt smell. I disregarded it thinking maybe its fresh paint burning , WRONG. Till this day 4 months later my tail pipe throws a musty smell. Issue number 2 , the hesitant gas pedal. Who knows what it is maybe fuel system , transmission but daily and I mean DAILY my accelaration is poor,jerky, struggling and overall doesn't work. It has its good mornings but once I'm on the road for more than 10 minutes its back to the struggle. I've had my K4 serviced twice at Dtla service, they never once test drove the car because I was tracking the GPS almost all day for the three days they had it. Once I got my car back it tooks about 45 minutes the service advisor Jeffery Montoya was so lost on where my car was, I had to ask and ask and ask finally the guys who are out front welcoming you helped me and brought my car. That was my decision to never go back to DTLA service. Next took it to Van Nuys Kia waited to weeks from my appointment because they are moving. Finally they kept it for three days they still werent able to diagnose the issue and repair it. Modesto the advisor there said " we can't duplicate the issue''. Some how they made me pay $82 because they supposedly found plastic bags stuck to my exhuast. [XXX] I even told him I don't want it cleaned and he said oh well you authorized the diag so you have to. He reported that info to kia Corp which got my case closed and said the car works fine. NO it does not work fine. Never going. Now today [XXX] I was parking arriving somewhere the k4 said engine off shift to P while ringing the alarm from the dash. I have it on film. Second driving down [XXX] and boom car engine shuts off while car are behind me. I had to shift to p then turn the car off. Turned it back on while getting honked at and that was that. $700 a month for a lack of urgency to help me. Boo Kia. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION