Ignition Switch on (Zero RPM)

PCM READS:

Atmospheric Pressure (MAP sensor)
Engine Temperature (ECT Sensor)
Throttle Position (TPS)

PCM OPERATION:

The PCM calculates basic start-up fuel strategy, using current; atmospheric pressure, engine temperature, and throttle position.

- PCM prepositions the idle air control motor.

- PCM energizes ASD and fuel pump relays for up to 3 seconds.

- PCM energizes oxygen sensor heating element.

NOTE: When the key is on and the engine is not running, the Automatic Shutdown (ASD) and fuel pump relays are deactivated after 1 to 3 seconds.