I'm expreiencing a no-start on my new L98 and need to know if the stock computer will run the engine with no EGR. Just wondering so I can take that off the list of things that could be wrong. I know if you push the vaccuum diaphragm on the EGR valve when the motor is running that it will shut itself off and I'm wondering if thats what is happening, just without the EGR valve in place. Thx.

 

Yes. I no longer have an EGR valve because my Performer intake has no provision for one. There is a little electronic solenoid for it which controls how much vacuum the EGR valve gets. I simply took mine off and left it unplugged, and it does not get a check engine light.

 

Yes. The ECM has no way of DIRECTLY knowing if the EGR valve is functional. At cruising speeds it can sometimes INFER that it has been deactivated by looking at other sensors and throw a Check Engine light (my 91 GMC Jimmy with TBI injection system takes about 3 minutes of steady highway cruising to pop a Check Engine light) but it will in no way cause a no-start condition.

 

Thanx guys. Now I can rule that idea out of the equation.

 

I should run if the valve isn't leaking. On my Crossfire eng, I made my own gasket under the EGR. My custom gasket had no holes, so it sealed off the ports, but everything looked stock.

On my 87 L-98 intake (my parts car), there's a small temp sensor installed right under the EGR.
I thought that if the sensor didn't see a rise in temp after valve was commanded open, it would throw a code. Not 100% sure abt that though.