OK, IVE POSTED ALOT WITH THIS NIGHTMARE BUT IVE ALMOST GOT IT.

Failed Emissions test with NOX very high.

I found the EGR valve is not getting vacuum with engine rpm increasing. The book says the ERG should see vacuum and the rpm increases.

I found the EGR vacuum solenoid has power but must not be getting a ground from the ECU. So what signals the ECU to create the ground to open these solenoids.

One big question is cant you simulate the vacuum while stationary or do you have to actually drive it? The book say just increase throttle.

As of right now I hot wired EGR so its open all the time. This should help me pass emissions tomorrow and ill switch back to the EGR not working at all.

Any help? What signals the ground to the ECU to send vacuum to the EGR?

 

Did you try pinching off that other vaccuum line that isn't a vaccuum line but rather sucking in air constantly? I didn't see any response on the other thread. Sometimes you have to think outside the box. This could be the reason why you are not getting much vaccuum. You've got so many threads and problems with your engine, it's hard to follow. Some issues could be affecting other areas such as what I said here. Your engine is not popular and it is hard to find good advice, so try something. Pinching off that line is an easy suggestion. Your engine won't blow because of it.

 

Your right about alot of post, thing is I fix one thing and another pops up.

Ill just cap off the fresh air line. And try it. The only reason I went towards EGR at all is not knowing exactly when I should see vacuum at it. The valve it working great. The book say run engine up and watch for vaccum. Well what is exactly run it up. Some threads say the engine needs to see a load such as accualy driving it with a gauge attached.

This car has been an absolute emissions nightmare. Im so close to getting fixed except the emissions test now. My NO are so high because the pre-cats at blown and can afford to replace at $600 each.

Going to try retarding engine and alcohol in gas and see how much it comes down.