If I unplug the rubber boot on top of egr valve and apply vacuum pump should the valve hold vacuum solid, gauge does not move? I am doing this with the car off and the gauge does not hold but i can hear the valve lose vacuum? The valve is negative backpressure..stamped N. 1995 M6..143K miles.

 

Yes, it should hold vacuum.

EGR

 

OK...so mine is broke since I can keeping applying trigger and gauge just keeps flapping and not holding solid. Neg backpressure valve hard to find..summittracing will not ship until 9/11/12. Any ideas where I might be able to pick one this labor day weekend.?

 

Have you tried any local part places. I would think it would be a common item.

 

I have to admit..not sure what kind of egr valve I have since last time I changed did not know about ported vs pos vs neg. I believe I have a neg bac pressure sys for may 1995 m6 vin p car model. How do I know what valve type if I never checked the stampings on the egr? What kind of egr sys in my car? Pos or neg or ported?

 

Just go buy what they say fits it. You don't need to worry about what kind it is. It should be the right one.