Possible causes

– Dirty throttle body
– Electric throttle control actuator misadjusted or damaged
– Faulty Electric throttle control actuator
– Intake air leak
– Poor electrical connection to the Intake Air Control (IAC) valve

Tech notes

If there are no intake leaks, clean throttle body, adjust engine idle and erase engine code. If the code comes back you may have to replaced the Electric Throttle Control Actuator (Motor) to repair the problem.

There is a factory service bulletin for the following GMC models:
2006-2008 GMC Envoy
2007-2008 GMC Savana
2007-2008 GMC Sierra
2007-2008 GMC Yukon
GMC Factory Service Bulletin OBDII Code P0507

When is the code detected?

Thi P0507 code sets when the Powertrain Control Module (PCM) detects an engine speed outside of the Idle Air Control (IAC) valve range of control.

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)
– Engine hard to start
– Rough or erratic idle speed

P0507 GMC Description

The Idle Air Control (IAC) valve is a Powertrain Control Module (PCM) controlled stepper motor located on the throttle body. The stepper motor drives a valve pintle which protrudes into a passage that bypasses the throttle plates. The PCM commands the IAC valve pintle to extend to decrease the idle speed. The bypass air flow is reduced and the idle speed decreases as the pintle approaches its seat. The PCM retracts the IAC valve pintle away from its seat to increase the idle speed. The retracting of the IAC valve pintle allows more air to bypass the throttle plates. One of the PCMs uses for the IAC system is to maintain a desired idle speed. This DTC sets when the PCM detects an engine speed outside of the IAC’s range of control.

GMC Technical Service Bulletins for P0507 code