Backpressure EGR cause 0 vaccum?

[yoyo13131]

Ok my vacuum at idle use to be at 9-11 HG but something changed and now I can't boost past 4psi and have ZERO vacuum at idle. I hear a huge boost leak but all hoses are still on tight, no holes on my FMCI and when I try to do a boost leak test all psi leaks out my EGR. I used a mighty vacuum pump to close the EGR and I could still hear psi leaking out of it.... And at no time the psi gauge holds steady, leaks all out.

Main question, can the dumb backpressure EGR cause 0 vaccum at idle? Over time my HG vacuum at idle has slowly decreased....Highest it's ever ever been is 12hg and my timing is verified twice to be good, same with ignition timing. Any help will be appreciated because I'm at the giving up point until I get rid of this 1988 engine to my 1993 fully built motor

1992 Dodge Shadow (1988)2.2 turbo 1 FMIC-TE04H-Stage 1SBEC-2.5 exhaust-Walbro 255-Vacuum block,non-turbo valve cover. Computer boost to 11 psi

[tryingbe]

Does your vacuum diagram have EGR? If not, you can get rid of EGR and pass smog...

[yoyo13131]

Quote:

Originally Posted by tryingbe Does your vacuum diagram have EGR? If not, you can get rid of EGR and pass smog...

My original diagram is for a 2.2 TBI. I turbo converted and already passed smog. My only concern is that i have ZERO vacuum at idle.

[tryingbe]

Quote:

Originally Posted by yoyo13131 My original diagram is for a 2.2 TBI. I turbo converted and already passed smog. My only concern is that i have ZERO vacuum at idle.

So, fix the vacuum problem by getting rid of the EGR.

Quote:

Originally Posted by yoyo13131 I try to do a boost leak test all psi leaks out my EGR.

Though, I am thinking your gauge have a vacuum leak in itself. If you are pulling 0 vacuum, the engine should be redlining itself and boucing off the rev limiter.

[yoyo13131]

Quote:

Originally Posted by tryingbe So, fix the vacuum problem by getting rid of the EGR. Though, I am thinking your gauge have a vacuum leak in itself. If you are pulling 0 vacuum, the engine should be redlining itself and boucing off the rev limiter.

I'll double check my phantom autometer gauge connections and buy a EGR block off plate and factor those two out but I dought it's gonna fix anything knowing the history of vaccum issues with my setup.

[Glhs60]

Quote:

Originally Posted by tryingbe So, fix the vacuum problem by getting rid of the EGR. Though, I am thinking your gauge have a vacuum leak in itself. If you are pulling 0 vacuum, the engine should be redlining itself and boucing off the rev limiter.

If the throttle is closed it can't rev past 3000 no matter how large the leak.

Thanks
Randy

[yoyo13131]

My idle is always been perfect and vacuum has no relation to RPM on my car. No matter where my HG has been my idles always been 900-1000rpm

[NAJ]

An engine cannot run at idle with 0"HG and 9-11" HG at idle is also an issue, if this was/is your normal reading something was definitely overlooked or the vacuum gauge you are using is not accurate.
Engine vacuum that low at idle will cause the vehicle to run "black" rich.

EGR is only an issue at idle if it is open when it is not supposed to be then the car will run very poorly.

READING A VACUUM GAUGE
How to Use and Interpret a Vacuum Gauge

[yoyo13131]

Well I figured out my 0 HG issue. The new adapter that goes from the autometers plastic tube to the orifice had a huge crack in it. Replaced it and now I'm back to my normal 9-11hg of vacuum and boosting to 11psi. Well once I get my new 1993 2.5 in my shadow without EGR hopefully my vacuum will magically be 20hg at idle.