mcgw1000

I experience the same problem on my 97 OBW. I was planning on bleeding/fushing the barke lines when things slow down a little but i did have an oppurtunity to remove the vacuum hose and blow it out last weekend. I pulled the car in the garage when I got home around 6PM on Friday (it was snow and ice covered). I did not get to it till afternoon on Saturday and when I pulled the vacuum lines, the diaphram was still holding vauum (evidenced by the whosh). Does anyone have any updates?

No, since the wiring goes around and under engine components I could not follow it. I was wondering if anyone knows if the computer operates the switch open and closed or if there is a problem. I checked the valve with a hand vacuum pump and it worked fine, also hooked it directly to the manifold vacuum and it opens when the car is running. If the switch is supposed to operate intermitently, it means there is a blockage between the crankcase and the valve (I did not disconnect the tubing).

Can anyone tell me why the EGR switch drops in and out while engine is running? History; My check engine light came on and the code was EGR Flow. I used a vacuum pump to check the valve and it was working normally. I checked the vacuum from the manifold and it moved with the speed of the engine, as normal. I then checked the vacuum between the switch and the valve and found it going on and off. It does it wether the engine is at lower RPM or reved to 3000 RPM and held. I have the switch bypassed right now so the EGR will operate directly off manifold vacuum and have not gotten the light back yet, although I am expecting it so I can recheck the code. Anyone come across this before?