EGR functionality

[james85z28]

what's a good test to see if the EGR valve is functional?

with the engine not running the valve holds vacuum.

with the engine running, I cannot get the valve to open and stumble the idle (using a vacuum pump). Is this correct. I remember a mechanic test an EGR valve before and applying vacuum to the valve caused the car to stall.

?????

[WS6 VERT]

Applying vacuum only works to non-backpressure valves. I have heard of people making it work by blocking the exhaust (not fully, but most of it)

The fact that it holds vacuum means the diaphram is OK.

[ June 02, 2002, 23:04: Message edited by: NOTaGTA ]

[RacerX]

stick your finger in one of the small holes and puch on it... if it moves freely it SHOULD be ok, but if its sticking or wont move at all you know its bad. The last one I put on my car only lasted a yr before it started codeing again, and sticking. Now its a paperweight, and a blockoff plate is in place.