EGR Valve: Testing and Inspection

1. Check vacuum diaphragm function by applying an outside vacuum source to vacuum supply tube at top of vacuum diaphragm. The diaphragm should not leak down and should move to the full up position at approximately 7 inches Hg vacuum.
2. Check EGR valve diaphragm for cracks. Replace EGR valve, if necessary.
3. Check for damage and carbon deposits around valve or seat. Replace EGR valve, if necessary.