Idle Speed: Adjustments

BASIC IDLE SPEED ADJUSTMENT

Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: USB Cable
- MB991911: Main Harness B

NOTE: The standard idle speed has been adjusted with the speed adjusting screw (SAS), by the manufacturer, and there should be no need for readjustment.

NOTE: If the adjustment has been changed by mistake, the idle speed may become too high or the idle speed may drop too low when loads A/C, defogger, etc. are placed on the engine. If this occurs, adjust by the following procedure.

NOTE: The adjustment, if made, should be made after first confirming that the spark plugs, the injectors, the idle air control motor, compression, etc., are all normal.




1. The vehicle should be prepared as follows before the inspection and adjustment.
- Engine coolant temperature: 80 - 95 degrees C (176 - 203 degrees F)
- Lights, electric cooling fan and accessories: OFF
- Transaxle: Neutral

CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.

2. Connect scan tool MB991958 to the data link connector (16-pin).
3. Start the engine and run at idle.
4. Select the item number 30 of the scan tool Actuator test.

NOTE: Use the scan tool to hold the IAC motor at the basic step to adjust the basic idle speed.

5. Check the idle speed.

Standard value: 850 ± 50 r/min

NOTE: The engine speed may be 20 to 100 r/min lower than indicated above for a new vehicle [driven approximately 500 km (300 mile) or less], but no adjustment is necessary.

NOTE: If the engine stalls or the engine speed is low even though the vehicle has been driven approximately 500 km (300 mile) or more, it is probable that deposits are adhered to the throttle valve, so clean it.




6. If not within the standard value range, turn the speed adjusting screw (SAS) to make the necessary adjustment.
7. Press the scan tool clear key, and release the IAC motor Actuator test mode.

NOTE: Unless the IAC motor is released, the Actuator test mode will continue for 27 minutes.

8. Turn the ignition switch to the "LOCK" (OFF) position.
9. Disconnect scan tool MB991958.
10. Start the engine again and let it idle for about 10 minutes. Check that the idling condition is normal.