Monte Carlo V6-3.4L VIN E (2000)
Idle Speed: Adjustments
The Powertrain Control Module (PCM) controls engine idle speed by adjusting the position of the Idle Air Control (IAC) motor pintle. The IAC is a
bi-directional motor driven by two coils. The PCM pulses current to the IAC coils in steps, counts, to extend the IAC pintle into a passage in the
throttle body to decrease air flow. The PCM reverses the current pulses to retract the pintle, increasing air flow. This method allows highly accurate
control of idle speed and quick response to changes in engine load.