Ok I pulled off the egr valve and cleaned it up good. then put it back on and checked to see if there was vacuum coming from the solenoid. how do i check the vacuum? just put my finger over the hose and see if it sucks? will it be easily noticeable if it is sucking? because i changed the solenoid with a new one and i still dont feel much vacuum. also when the engine revs i dont feel the diaphram moving. so is my valve bad?