Idle Speed: Adjustments

The Powertrain Control Module (PCM) controls all Idle Speeds, and is therefor not adjustable.

NOTE: The air entering into the engine is controlled by the PCM, with an Idle Air Control (IAC) valve. To increase the idle rpm, the PCM commands the pintle inside the IAC valve away from the throttle body seat. This allows more air to bypass through the throttle blade. To decrease the rpm the PCM commands the pintle towards the throttle body seat. This reduces the amount of air bypassing the throttle blade.