Emission Control Systems: Adjustments

Idle Speed Setting:

1. Disconnect idle speed control-air bypass solenoid.
2. With transmission in Neutral or Park, run engine at 2500 rpm/30 seconds.
3. Allow engine to idle for 2 minutes. If engine stalls, turn throttle stop screw one turn clockwise, then repeat steps 2 and 3.
4. Place automatic transmission in Drive; manual transmission in Neutral.
5. Check/adjust idle rpm:
Turn the throttle plate stop screw to 600-650 rpm for automatic transmission, 700-750 rpm for manual transmission.
6. Shut engine off and repeat Steps 2, 3, 4, and 5.
7. Shut engine off and disconnect battery for a minimum of 5 minutes.
8. With the engine off, reconnect the idle speed control-air bypass solenoid, verify the throttle is not stuck in the bore, and the linkage is not preventing throttle from closing.
9. Repeat steps 2 and 3. Let engine idle for 2 minutes, then repeat steps 2 and 3 again. Let engine idle for 1 minute and check curb idle speed.