Tl* the contact owns a 2016 kia rio. when the accelerator pedal was depressed, the vehicle failed to accelerate, but the engine continued to operate. there were no warning indicators illuminated before or after the failure. the failure was experienced numerous times while at a stop or traffic light. the accelerator pedal had to be depressed several times to accelerate. the vehicle was taken to team kia (1215 scalp avenue, johnstown, pa 15904, 814-266-8611) where the dealer test drove the vehicle; however, the failure was unable to be duplicated. the vehicle was diagnosed, but a failure code was not located. the dealer determined that the failure occurred due to low grade fuel. the vehicle was not repaired. the manufacturer was not notified. the failure mileage was 915.