Operation CHARM: Car repair manuals for everyone.
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A/C Idle Boost System

Fig. 21 Idle Boost Throttle Controller:






This system is used on A/C equipped vehicles only.

1. Disconnect vacuum hose from idle boost throttle controller and connect vacuum gauge.
2. Start engine and check gauge.

Expected result:
No vacuum. If OK continue. If not OK refer to testing procedures outlined in COMPUTERIZED ENGINE CONTROLS.

3. Turn on air conditioning. Check gauge.

Expected result:
Engine vacuum. If OK continue. If not OK refer to testing procedures outlined in COMPUTERIZED ENGINE CONTROLS.



4. Connect vacuum pump to open idle boost throttle controller port and apply vacuum.

Expected result:
Holds vacuum. Idle speed increases.

5. If unit held vacuum but speed did not increase, refer to ADJUSTMENT PROCEDURES. If the diaphragm did not hold vacuum throttle controller is defective and must be replaced.