P0638 GMC Throttle Actuator Control Range/Performance
Possible causes
– Drive-by-wire control system malfunction
– Throttle actuator malfunction
– Throttle valve malfunction
– PCM malfunction
– Throttle actuator malfunction
– Throttle valve malfunction
– PCM malfunction
Tech description
Dirty or clogged throttle body can triggered the P0638 GMC code. Before replacing any parts try cleaning the throttle body and reset the engine light.
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
P0638 GMC Description
The Powertrain Control Module (PCM) compares the actual Throttle Possition (TP) with the target TP when the engine is running. If the difference is more than the specification, the PCM determines that there is a throttle actuator control circuit range/performance problem.
GMC Vehicle:GMC Acadia,GMC Canyon,GMC Envoy,GMC Savana 1500,GMC Savana 2500,GMC Savana 3500,GMC Sierra 1500,GMC Sierra 2500 HD,GMC Sierra 3500 HD,GMC Terrain,GMC Yukon,GMC Yukon XL 1500,GMC Yukon XL 2500,