W350 1 Ton Pickup 4WD V8-360 5.9L VIN 1 4-bbl (1988)
Idle Speed: Adjustments
Curb Idle Speed Adjustment
NOTE: Before checking or adjusting the idle speed check the ignition timing and adjust if necessary, refer to IGNITION SYSTEMS/ADJUSTMENT
PROCEDURES for correct procedure.
1.
Remove the air cleaner, and plug the heated air hose. Disconnect and plug the vacuum hoses at the distributor and EGR valve. Disconnect and
plug the canister purge hose at the canister.
2.
Remove the PCV valve from the cylinder head cover, and allow the PCV valve to draw under hood air.
3.
Install a tachometer and START and run the engine until normal operating temperature is achieved.
4.
Place the transmission in NEUTRAL, and set the park brake securely. Note the idle speed on the tachometer.
5.
If the idle speed is not correct, turn the idle speed screw to obtain 800 rpm for heavy and/or light duty vehicles, and 750 rpm for high altitude
vehicles.
6.
Place the vehicle in PARK, STOP the engine, remove the tachometer, unplug and reconnect all hoses, reinstall the PCV valve and the air cleaner.
NOTE: Idle speeds with the engine in normal operating condition may vary from set speeds. Do not readjust the idle speed.
