T90

Kind of loing, but please read through

Today in an effort to once again diagnose my rough idle problem I pulled the codes, once again I got the usual CMP and injector codes but I also got an EGR code.

After printing off a vaccuum diagram from Alldata, I made sure my EGR Frequency valve was correctly plumbed in, and it was, so I followed the hose back to the EGR checking for cracks etc., there were none. When I took a closer listen to the intake sound as the car was running though, it sounded like there was a leak coming from the throttle body or the TB was just sucking a lot more air, so I disconnected the EGR vaccuum line and the idle smoothed right out, plugged it back on and the idle got rough again and the leaking sound came again.

I checked and retightened the bolts that hold the ERG to the intake but it made no difference. So with the EGR unplugged the car runs perfectly and idles smoothly, but with the EGR receiving vaccuum the idle gets very rough.... what could the reasoning be.

4kqlifer

I recently cleaned my egr passage and when I had the car back together it idled like crap. It had a loud vacuum leak that I couldn't place. I finally looked carefully at my egr valve and I misaligned the new gasket while reinstalling it. It was hanging in midair by the top bolt only. I redid it and it ran perfect. Maybe your problem??

T90

Just a quick thought, could it be my EGR vaccuum regulator solenoid valve is not operating properly? The EGR should not have vaccuum at idle should it?