C 1500 Truck 2WD V8-5.3L VIN T (1999)
Engine Control Module: Service and Repair
Idle Learn Procedure
IDLE LEARN PROCEDURE
Anytime the PCM or the battery is disconnected, the PCM loses power, or the PCM is reprogrammed, the PCM's learned idle position is lost. The
engine idle is unstable when the learned idle position is lost. Perform the following procedure in order to return the learned idle to the correct position:
AUTOMATIC TRANSMISSION
1. Turn OFF the ignition.
2. Restore the PCM battery feed.
3. Turn OFF the A/C controls.
4. Set the parking brake and block the drive wheels.
5. Start the engine.
6. Engine coolant temperature greater than 80°C (176°F).
7. Shift the transmission selector into the drive range.
8. Allow the engine to idle for 5.0 minutes.
9. Shift the transmission selector into the park range.
10. Allow the engine to idle for 5.0 minutes.
11. Turn OFF the engine for 30 seconds.
MANUAL TRANSMISSION
1. Turn OFF the ignition.
2. Restore the PCM battery feed.
3. Turn OFF the A/C controls.
4. Set the parking brake and block the drive wheels.
5. Transmission in neutral.
6. Start the engine.
7. Engine coolant temperature greater than 80°C (176°F).
8. Allow the engine to idle for 5.0 minutes.
9. Turn OFF the engine for 30 seconds.
