The idle air control on an Isuzu Trooper is a valve that opens and closes to meter the air flowing into the throttle at idle. When the Trooper is not idling properly, this is a major cause. There is no service life for the idle air control valve, so you replace it only when the idle begins to fluctuate wildly. The fluctuating idle indicates a complete failure of the valve.
Tools Used: Tools, Socket wrench, 10mm socket, Screwdriver
Replace Idle Air Control
Disconnect the negative cable running to the negative battery terminal. Loosen the retaining nut on the negative lead and slide the clamp off the battery terminal.