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Idle Speed/Throttle Actuator - Electronic: Testing and Inspection

SYSTEM INSPECTION

System Inspection:






1. Start engine and run at idle.
2. Ground test connector (Green: 1 pin).
3. Unplug BAC valve electrical connector. Idle speed will be slower than normal
4. Pinch off air hose and note idle speed. On a cold engine, rpm should drop. On a warmed up engine, rpm should remain unchanged.
5. Reconnect BAC valve connector, ensure that engine is at operating temperature and run at idle.
6. Check that idle speed is 650 ± 20 rpm in "P" range.
7. Unplug BAC valve electrical connector and ensure that engine speed decreases.
8. After checking, replace BAC valve connector and disconnect check connector ground wire.

AIR VALVE

Air Valve Check:






1. Disconnect air hoses from air funnel.
2. Blow through valve and check air flow. With engine cold, air should flow. With engine at operating temperature, air should not flow.
3. If not as specified, replace BAC valve assembly.

IDLE SPEED CONTROL (ISC) VALVE

ISC Valve Resistance Check:






1. Unplug ISC valve electrical connector.
2. Check resistance across terminals. It should be 10.8 - 12.3 ohms.
3. If not as specified, replace BAC valve assembly.