2019 Kia Niro Fuel System Problems

While traveling from upstate New York, the vehicle displayed an engine overheating warning shortly after startup while the engine was still cold. Because I was away from home, I stayed overnight and the next morning took the vehicle to a Kia dealership for inspection. The dealership inspected the vehicle and diagnosed a problem with the exhaust heat recovery system pipe. According to the service department, coolant is leaking internally through this component and is being burned in the exhaust system. The cooling system was pressure tested and held pressure externally, indicating the coolant loss is occurring internally through the exhaust heat recovery system rather than from an external leak. This condition can cause coolant loss and overheating while driving. If the engine overheats while the vehicle is in operation, it could create a safety risk due to sudden loss of power or engine damage. The dealership confirmed the diagnosis after inspection and testing and provided a repair estimate to replace the affected exhaust heat recovery system component. The overheating warning message was the first symptom observed prior to diagnosis. The problem was confirmed by the dealership after inspection and testing. This issue may indicate a defect in the exhaust heat recovery or thermal management system used in this hybrid vehicle, as coolant is entering the exhaust stream internally rather than leaking externally. If this type of failure occurs in other vehicles, it could lead to overheating while driving and potential engine damage.

There is a pause upon acceleration from a stop (unresponsive). Then the vehicle will lunge forward and make a loud noise. For both driver and passengers, it can be quite startling and feels as though the car has been hit from behind. This started happening in the fall of 2021, when the car was about two years old with about 18,000 miles. It has happened about a dozen times in the six months since first noticed. It seems that this may be a software issue related to the hybrid system - a lag in triggering which motor to use for acceleration.

AS I WAS DRIVING ON THE HIGHWAY, THE AC STOPPED WORKING. THERE WERE NO WARNING LIGHTS, ALARMS OR INDICATORS THAT SOMETHING WAS WRONG, BUT I IMMEDIATELY GOT OFF THE HIGHWAY BECAUSE I THOUGHT THIS IS NOT RIGHT. AS I BRAKED ON THE RAMP, THE CAR STILL WORKED, BUT WHEN I TRIED TO ACCELERATE LEAVING THE RAMP, THERE WAS NO POWER. I GOT INTO AN ADJACENT PARKING LOT AND TURNED OFF THE CAR. WHEN I TRIED TO TURN IT BACK ON, IT WAS COMPLETELY DEAD. I CALLED AAA, THEY GAVE IT A JUMP, BUT EVEN THOUGH THE BATTERY WAS FULL, WHEN PUT INTO DRIVE OR REVERSE IT WOULD DO NOTHING.