Carbureted Engine

1. Start engine and allow to idle.






2. Disconnect # 16 vacuum hose from Exhaust Gas Recirculation (EGR) valve and connect a hand vacuum pump to EGR valve.
3. Apply 150 mm Hg (6 in.Hg) vacuum to EGR Valve. Vacuum should remain steady and engine should die.
^ If vacuum remains steady and engine dies, EGR valve is working properly. Remove hand vacuum pump and reconnect EGR vacuum hose, test complete.
^ If vacuum does not remain steady and engine does not die, replace EGR valve and retest.
^ If vacuum remains steady but engine does not die: Remove EGR valve; check EGR valve and manifold for blockage, clean or replace as necessary and retest.