2026 Kia K4 Owner Complaints

The contact owns a 2026 Kia K4. While driving 37 MPH, the vehicle lost motive power. After restarting the vehicle, the failure persisted, and the message "Press Engine Start/Stop" was displayed with the key warning light illuminated. The following night, the contact started and then turned off the vehicle; however, the vehicle restarted independently without the Engine Start/Stop button being pressed. The vehicle was towed to the dealer but was not yet diagnosed. The manufacturer was notified by phone, and a case was filed. The failure mileage was 25,352.

NHTSA ID

11769857

Incident

Oct 6, 2026

Mileage

25,352 mi

On August 26, 2026, at approximately 5:30 PM, while driving home from work at about 55 MPH, the factory panoramic sunroof glass of my brand-new 2026 Kia K4 spontaneously shattered and catastrophically exploded without any external impact. The sudden, deafening blast sounded like a gunshot or like another vehicle had crashed into me, though I felt no physical impact. This intense noise created an extreme safety hazard as I swerved due to a panic reaction, and could have lost control of the vehicle, or caused a multi-car collision during rush hour traffic. Fortunately, the interior sunshade fabric was completely closed at the time, which prevented the shattered tempered glass from showering into the cabin and causing immediate cuts or blindness. Immediate photographic documentation taken right after pulling off the freeway clearly shows the remaining glass bowing upward and outward, confirming a structural, manufacturing, or cabin-pressure failure rather than an impact from road debris. There was even glass debris found on my back windshield near my trunk. There were absolutely no warning lamps, error messages, unusual wind noises, rattling, or prior symptoms of any kind leading up to the incident. The vehicle and the failed component were delivered to an authorized Kia dealership service department on August 27, 2026, where the total failure was confirmed and where the vehicle remains available for inspection upon request. The car has now been in the physical possession of the manufacturer's dealership for 32 consecutive days; however, Kia Corporate Customer Care has repeatedly delayed the case, changed case managers, and failed to provide any communication. Furthermore, a close contact of mine recently experienced an identical spontaneous sunroof explosion on a highway while driving a Kia vehicle, indicating a broader, systemic safety hazard with Kia panoramic sunroofs.

NHTSA ID

11767571

Incident

Aug 26, 2026

Driving home, the entire screen flickered, then went out, when it came back the drivers assist lane assist kicked in and the car steered itself into oncoming traffic, which forced an oncoming car in front had to lock its brakes to avoid a collision. Then after forcing the steering out of the incoming lane, the lane assist came back on causing collision with the curb in the opposite direction. After resetting the computer with a pin, and watching the screen flicker and blink, it came back on and now the car is parked at home. Hewitt police would not come out because it was in Waco (the car is garaged in Hewitt), and Waco police said it was not in their jurisdiction so no police report was made.

NHTSA ID

11767387

Incident

Sep 27, 2026

On August 28, 2026, I was driving my 2026 Kia K4 GT-Line with approximately 1,872 miles at low speed in a parking lot. While making a left turn at the end of an aisle, I attempted to straighten/unwind the steering wheel. The steering became unusually unresponsive and I was unable to straighten the vehicle as expected. The vehicle continued left and struck a curb, causing body and front suspension damage. The abnormal steering behavior occurred before the curb impact. I observed no power steering, check-engine, ADAS, or other warning lights or messages before or during the incident. An authorized Kia dealer inspected the vehicle before collision repairs. The dealer documented my report that the steering became very unresponsive before the vehicle contacted the curb. The technician scanned the vehicle and reported finding no active or stored diagnostic trouble codes and no evidence of abnormal loss of power steering at the time of inspection. The dealer also determined that the right-front suspension sustained extensive collision damage and that the vehicle was unsafe to drive. Because of this damage, the vehicle could not be road-tested to attempt to reproduce the steering condition. The cause of the abnormal steering behavior remains UNKNOWN. I am not claiming that a particular steering component has been confirmed defective. I am reporting this because the steering became abnormally unresponsive before the collision, resulting in loss of my ability to follow the intended path of travel and creating a safety risk. The vehicle was made available to the Kia dealer for inspection before collision repairs.

NHTSA ID

11765622

Incident

Aug 28, 2026

The vehicle has repeatedly jerked into other lanes while I am driving, requiring me to quickly jerk the steering wheel back to avoid a collision. This occurs whether the lane-keeping assistance feature is turned on or off. I turned the feature off, but the problem continued. The vehicle does not feel safe to drive and appears likely to cause an accident, especially when there is oncoming traffic.

NHTSA ID

11765205

Incident

Sep 18, 2026

Was in a side impact collision on july 17, 2026, vehicle was totaled but no air bags deployed nor did any collision sensors go off

NHTSA ID

11762542

Incident

Jul 17, 2026

The vehicle issues began 3 weeks after purchasing a 2026 Kia K4 with 89 miles on it. *"Key fob not recognized", black screen, car not starting and cascading into many other infotainment problems. ** Revving far higher (1.4 - 4.4) with the slightest acceleration ***Hesitating, them engaging so suddenly that steering is incredibly difficult. On more than one occasion, of someone had been in front of me, I would have hit them. ****All steering assist options OFF yet the car will take control and turn me towards oncoming traffic. I absolutely could have been in/caused a serious accident. •We have had it into the service department 3 times and they were "unable to replicate" in spite of the fact that the second technician was unable to lock/unlock the door while my husband was standing with him. They refused to see the videos that we had of some of the problems.They lied about how far it was driven. 2 of the visits the average speed limit was 23 and 25 mph. Total miles driven: 11 v/s the 39 reported. One visit claims 4 miles but our app shows nothing for the time it was being looked at. •I have asked many times if the computer system had been checked for error codes or glitches and no one will answer the question. •No warning lights, just MANY obvious computer system problems

NHTSA ID

11755719

Incident

Jul 10, 2026

The contact owns a 2026 Kia K4. The contact stated that on several occasions while driving at various speeds with the smart cruise control activated, the brake was applied inadvertently and the steering wheel steered to the right, overcorrecting his steering efforts. The contact state that the inadvertent braking and steering nearly caused the vehicle to crash and almost resulted in the vehicle being rear-ended by another vehicle. The vehicle was taken to a dealer where it was diagnosed that the vehicle operating normally and there was no failure replicated. The manufacturer was notified of the failure and multiple complaints were filed. The failure mileage was unknown.

NHTSA ID

11741355

Incident

May 5, 2026

My car was brand new with only 1442 miles. I was hit in the rear passenger side at a four way stop, this was not much force, however I was injured and my car was deemed a total loss. I fear this car ranks low in safety. Thankfully my daughter was not with me at the time.

NHTSA ID

11739871

Incident

May 1, 2026

The contact owns a 2026 Kia K4. The contact stated while her daughter was driving at approximately 25 MPH, the lane assist feature was diabled however, the contact attempted to avoid a dog and the vehicle independently jerked the vehicle and caused the front driver side of the vehicle to crash into a fence. No warning lights were illuminated. The air bags were not deployed. The vehicle was taken back to the residence. A police report was filed. The vehicle was not diagnosed or repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 465.

NHTSA ID

11738505

Incident

May 17, 2026

Mileage

465 mi

Sometimes when I’m driving the steering wheel just jerks to the left sometimes causing me to swerve into incoming traffic. It’s very scary. Luckily I’m holding tight to the steering wheel to keep myself from hitting someone.

NHTSA ID

11733624

Incident

Apr 24, 2026

Steering Instability: The steering wheel would periodically veer to the right and left on its own without my input. This created an unsafe driving condition and required constant correction to maintain control of the vehicle. Blind Spot / Reverse Detection Malfunction: When shifting the vehicle into reverse, the dashboard display indicated that no vehicle was present. However, when visually checking my driver-side mirror, there was clearly a vehicle immediately adjacent to my car. The system failed to detect or warn of the nearby vehicle, creating a significant near missed accident and safety risk.

NHTSA ID

11720323

Incident

Feb 19, 2026

transmission stopped working when the vehicle was used under 200 miles.

NHTSA ID

11718955

Incident

Feb 15, 2026