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Idle/Throttle Speed Control Unit: Testing and Inspection

BAC VALVE

Air valve system inspection
1. Verify that the engine coolant temperature is below 20°C (68° F).

SST:




2. Connect the SST to the data link connector.
3. Set the system select to position 1 and test switch to SELF TEST.
4. Start the engine.
5. Verify that the idle speed decreases gradually as the engine warms up.

Air valve inspection
1. Remove the BAC valve.

BAC Valve Inspection:




2. Circulate water in the BAC valve coolant passage to cool the air valve.
3. Circulate hot water in the BAC valve coolant passage and verify that the air valve operates.
4. If not, replace the BAC valve.

Idle air control valve
1. Remove the throttle body.

IAC Valve Ohms Test:




2. Measure the resistance of the idle air control valve.

Resistance: 1O.7-12.3 Ohms @ 20°C (68°F)

3. If not as specified, replace the BAC valve.