Non-Turbo
- Check vacuum hoses for correct routing. Warm engine to operating temperature. Some models with EGR delay timers must run for at least 1-2 minutes before EGR works.
- While observing EGR valve stem, abruptly accelerate engine to 2000-3000 RPM. EGR valve stem should move at least 1/8". Repeat test to confirm operation.
- Connect a hand-held vacuum pump to EGR valve. Idle engine and gradually apply at least 10 in. Hg. EGR valve stem and diaphragm should move smoothly and engine speed should drop at least 150 RPM. If engine speed does not drop, check for plugged EGR passage.
EGR System Operation Check
- Warm engine to operating temperature. Check condition of all EGR system tubes, hoses and electrical connections.
- Start engine. Snap throttle to 2000-2800 RPM and check for EGR valve stem movement. If EGR stem moves, proceed to EGR GAS FLOW TEST. If no stem movement occurs, see TESTS W/CODES - 3.0L article in the ENGINE PERFORMANCE section for further testing procedures.