Computers and Control Systems: Adjustments

IDLE SPEED

Fig. 91 Electronic Air Control Valve (EACV) Location:

1. Start the engine and let it warm up to normal operating temperature (the cooling fan comes on).
2. Connect a tachometer.
3. Disconnect the 2P connector from the EACV.
4. Set the steering in the straight forward position, check the idle speed in the no load condition, with the headlights, cooling fan, and all accessaries are OFF.

Idle Speed Should Be:

Manual: 650 ± 50 rpm
Automatic: 650 ± 50 rpm (in "N" or "P")

Adjust the idle speed by turning the adjusting screw on top of the throttle body.

Fig. 92 Idle Speed Adjusting Screw Location:

5. Reconnect the 2P connector to the EACV, turn the ignition switch OFF, remove the CLOCK (10 Amp) fuse in the underhood relay box for 10 seconds to reset the ECU.
6. Set the steering in the straight forward position and check the idle speed in the no load conditions in which the headlights, blower fan, rear defroster, cooling fan, and air conditioner are not operating.

Idle speed should be:

Manual: 750 ± 50 rpm
Automatic: 790 ± 50 rpm (in "N" or "P")

7. Check the Idle speed in the following conditions.
a. With headlights ON (HI) and the rear window defogger ON.
b. While the steering wheel is turning.
c. If applicable, with Automatic transmission models in gear (except N or P)

Idle speed should remain stable at: 750 ± 50 rpm

8. Check the idle speed with the heater fan switch on HIGH (right end), air conditioner ON.

Idle speed should be: 750 ± 50 rpm

9. If the idle speed is not within spec., see "DIAGNOSIS BY SYMPTOM" under "COMPUTERIZED ENGINE CONTROLS".