Idle Speed: Adjustments

Because idle speed is ECU controlled through the idle speed control (ISC) valve, it is not usually necessary to check and adjust idle speed. However, grounding the test connector disables ECU idle speed control. If rough idling due to low rpm occurs when test connector is grounded, idle speed should be adjusted.

PREPARATION

1. Check engine condition (spark plugs, leaks in hoses, etc.).
2. Turn all accessories "OFF."
3. Warm engine to operating temperature.

ADJUSTMENT

1. Connect a tachometer.

Diagnostic/Data Link Connector:

2. Bridge "TEN" and "GND" terminals of diagnostic connector with a jumper wire.
3. Check that idle speed is within specification:

670 ± 30 rpm in neutral or "P" range

Adjusting Base Idle Speed:

4. If idle speed is not within specification, correct by turning air adjusting screw.
5. After adjustment, disconnect jumper wire from test connector.