Idle Enrichment Time Delay Test

1. Stop engine and then restart. Immediately open throttle to about 1,000 rpm and observe EGR valve stem for movement.
2. If EGR valve moves within the first 30 seconds after starting, the EGR time delay system is defective.
3. Check hose connections to the time delay solenoid valve. Disconnect electrical plug from solenoid valve and energize valve by grounding either terminal and connecting other terminal to battery positive. If EGR valve stem now moves, the solenoid is defective and should be replaced. If EGR valve does not move, EGR valve timer may be defective, or there may be a problem in the wiring harness.
4. If control system is functioning properly, the valve and passages may be checked for exhaust gas flow as described previously.