Idle Speed And Mixture Adjustments

IDLE SPEED ADJUSTMENT

NOTE: Idle speed is controlled automatically by the ECU through the Idle Speed Control (ISC) solenoid valve. Idle speed adjustment is usually not necessary.

1. Check the ignition timing and adjust to specification, if necessary.
2. Turn off all lights and other unnecessary electrical loads. Idle speed adjustment must be done while the radiator cooling fan is not operating.
3. Set the parking brake and place the transaxle selector lever in neutral on manual transaxle vehicles or P on automatic transaxle vehicles. Warm up the engine.
4. On all engines except 1995–98 2.0L (FS) engines with automatic transaxle, connect a jumper wire between the TEN terminal and the GND terminal at the underhood test connector.
5. On 1995–98 2.0L (FS) engines with automatic transaxle, remove the shorting bar from the double wire SPOUT connector.

   Fig. 1: To adjust the idle speed, turn the Air Adjustment Screw (AAS), NOT the throttle stop

6. Attach a suitable tachometer according to the manufacturer's instructions.
7. Check the idle speed. It should be within specifications.
8. If the idle speed is not correct, adjust the idle speed by turning the air adjusting screw.

   WARNING
   Do not tamper with any other adjustment screws. Doing so may result in damage to the throttle body.

9. After adjusting the idle speed, disconnect the jumper wire from the test connector or install the shorting bar.
10. Remove the tachometer from the engine.