Operation CHARM: Car repair manuals for everyone.

Idle Speed: Adjustments

Important: When the vacuum hoses have been disconnected and the system components have been removed for service, be sure to reinstall the components properly and reconnect and route the hoses correctly. Refer to Vehicle Emission Control Information Label for the proper routing of the vacuum hoses.

PROCEDURE
1. Check the accelerator cable for free movement and excessive play. Cable free play should be within specification. Refer to Engine Fuel.
2. Inspect the lead wires and the hoses of the Sequential Multiport Fuel Injection (SF1) and the Evaporative Emission (EVAP) control systems for being connected securely.
3. Check the ignition timing. Adjust the timing if necessary. Refer to Ignition System.
4. Turn OFF all accessories (A/C, wipers, heater, lights, etc.).
5. Make sure that the Air Cleaner (ACL) is installed correctly.


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6. Remove the cover on the idle speed adjusting screw (3).

ADJUST
^ Start the engine.
^ Allow the engine to reach normal operating temperature (accessories OFF).
1. Connect a scan tool.
2. Monitor the engine speed.

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3. Connect a jumper from terminal 2 (diagnostic request) in the Duty Check Data Link Connector to terminal 4 (ground).
4. Connect a DMM (J 39200) from terminal 6 (duty check) in the Duty Check Data Link Connector to Terminal 4 (ground).

Important: The AC duty can be checked by using a DMM (J 39200) in the D/C position. To convert the voltage reading obtained with the DMM to a percentage reading use the following formula: 0.5 x voltage (indicated on DMM) = duty percentage.

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5. Check the idle speed and the IAC duty. The IAC duty should read 50 percent (7V) with the correct engine idle speed. Refer to the idle Speed Setting table.
6. Adjust the idle speed as necessary.
7. Correct the idle speed by turning the idle speed/Idle Air Control (IAC) duty adjusting screw.
8. Remove the jumper from the duty check data link connector and DMM.
9. Disconnect the scan tool.
10. Install the idle speed/Idle Air Control (IAC) duty adjusting screw cover.
11. Check that the specified idle speed is obtained with the A/C ON (If equipped with A/C). Refer to the Idle Speed Setting table. If the idle speed is not as specified, check A/C idle-up circuit and Idle Air Control (IAC) valve circuit.