EGR Valve: Testing and Inspection

EGR Valve Testing:

1. Warm up engine and run at idle.
2. Disconnect vacuum hose from EGR valve and connect a hand vacuum pump to the valve.
3. Apply vacuum of 3.9 inHg (100 mmHg) and ensure engine speed decreases.

EGR Valve:

4. If not, remove EGR valve, clean passages and ensure that valve plunger operates freely. Replace EGR valve if passages cannot be cleared or valve does not function smoothly.
5. Clean out any carbon that may be blocking intake manifold exhaust passage. If available, use a vacuum cleaner to prevent carbon particles from falling into manifold.