EGR Valve
- Start and run engine at idle. Detach EGR valve vacuum hose from valve. Attach EGR hose directly to manifold vacuum source. Engine should stall or idle roughly.
- If not, turn engine off and remove EGR valve and pipe from engine. Clean passages with brush and wire. Reinstall items and repeat test. If engine still does not run rough or stall, replace EGR valve. When system functions as indicated, return vacuum hose to original position.