Diesel Data: Automotive Repair

California

FAST IDLE SPEED ADJUSTMENT
1. Place the transmission in Neutral or Park.
2. Bring engine to normal operating temperature (upper radiator hose hot).
3. Disconnect the vacuum hose at the EGR valve and plug.
4. Disconnect the vacuum hose at the purge valve and plug.
5. Disconnect vacuum hose from cold start vacuum switch (orange vacuum switch on rocker cover) and plug hose. Using a slave vacuum hose connect manifold vacuum to cold start vacuum switch.



6. Place the fast idle screw on the second step of the fast idle cam. Adjust fast idle speed to specification. Specifications
7. Remove plug from EGR valve hose and reconnect.
8. Remove plug from purge valve vacuum hose and reconnect.
9. Remove slave vacuum hose from cold start vacuum switch and manifold vacuum source.
10. Remove plug from cold start vacuum switch hose and reconnect hose to switch.