I'm currently getting a p0400 and have been cleaning and replacing parts like crazy. Now I'm down to just finding the clog if I can. My vacuum lines work great and the EGR solenoid is new and operating correctly. I am now where I cleaned my return line from my exhaust and that is clear too. after it goes back into the intake manifold this is where it gets hazy. I asume it comes out the bottom of the EGR valve and up through that port on top but I'm not getting anything at all coming out that tube up top. The EGR Valve is also new. Is my problem inside the intake manifold or where ever my return air is going?

 

what year and motor.

 

I just put on my Sherschlock Holmes cap, and elementary deductions told me he has a 96 Z28!

 

should check your connection at the solonoid. try pushing the valve in the egr open when its running or rent/buy a vacuum pump to test that way. add vacuum or open egr and if the idle changes its getting air through the passages. we did have a guy on here that finally changed intake manifold and that made it go away. now that could have been a intake gasket failing or cracked or plugged manifold.

 

what's an EGR ;-)

 

Oh, shame on you craby, you forgot to say "EGR valve"!!

 

yeah I get hessitation when I press in the diaphram. So I guess I am getting output out of the Valve. I guess I should start concentrating on the solenoid then. I took it off and put jumpers on it ot hear if it clicks over and opens up. It does all that so I'm thinking I'm going to have to trance the harness to the source and get my multimeter out. I've cleared out the code a few times with my code reader so I would can only assume that it does work. maybe I'll swap out my solenoid again in case it's the signal coming from it. I'm at a loss more so now LOL.