Good luck applying vacuum to that valve.
This vehicle uses the same digital egr valve that gm uses on its 4.3 vortec motor.
1. Did you use an oem valve with a new gasket?
2. Chances are the egr passage is blocked close to the intake side. Blowing into the passage will not help, the intake will need to be removed and cleaned.
Monday, January 28th, 2008 AT 8:19 PM