Idle Mixture, Adjust

1. Apply parking brake and block drive wheels, then place transmission in neutral, if equipped with manual transmission, or Park if equipped with automatic transmission.
2. Start engine and allow to reach normal operating temperature.
3. On models equipped with A/C, place A/C switch in Off position.
4. On models equipped with power steering, place front wheels in straight ahead position.
5. On all models, turn lights and all accessories Off.
6. Ensure Check Engine light is off.
7. Ground ``Test'' terminals A and C of the ALDL connector.
8. Gradually increase engine speed to over 2,000 RPM to reset position of the Idle Air Control Valve.
9. Set idle adjust screw to 900 RPM then recheck steps 7 and 9.
10. Remove test terminal ground and clear any ECM trouble codes.