thanks Dave, your advice really is sound when you suggest to replace all vacuum hoses. I'm going to follow it as quick as I have this problem sorted out. I know that one hose pictured doesn't leak, yet. it will be replaced as quick as I have a running car.

I checked the o ring around the mixture screw, perfect condition.

I even got a length of hose like previously suggested.. put one end to my ear and traced different lines with the other end. to get the engine to stay running, the throttle cable needs to be clamped, making the rpm so high that i couldn't hear clearly enough... the engine sound was all i heard in the hose.

I'm to the point where I've checked all my lines (the ones visible without taking out the intake manifold)... and i'm ready to pay a garage an hours worth of time to diagnose the location of the problem... it's obvious this goes beyond my (very) limited skill set..

Eldorado... also examine the corrugations of the Jboot, top and
underneath. Especially the 'valleys'.


G'luck.

If you have a compressor........... Plug up the intake opening...........and set the compressor for 15-30 psi may need higher depending on size of leak)........

and try and blow air through a vacuum hose....... and alternate through different hoses......

You will definitely hear it........... You will obviously loose air through the exhaust side (or try an set all exhaust valves to closed)........... but hey........... you are desperate.

:D

thanks alex... it's a great suggestion..
I always could plug up the exhaust pipe too.. lol

question...
what does that mixture screw change?
i can get the noise to be MUCH (and i mean maybe twice or 3 times) as loud as it is normally just by turning that screw...
what happens when i turn that screw, and how does it affect the intake?

you may be hearing the air flowing through the AFM. i know mine is loud. i think your vacuum leak is elsewhere... if you even have one. too bad you don't live near me. i'd tear that thing down and find the problem.

feel like taking a trip? ;)

i would love to take a trip. i haven't left utah in over a year.

Are you sure the idle adjusting screw's housing isn't cracked? If turning that screw makes a difference to what you're hearing, I'd have a really close look there for sure. Perhaps try to seat the screw all the way in, start the car and hang it on the throttle till you've backed the screw out far enough for it to hold an idle.

I've got a spare throttle body here if need be. Somewhere... And a J-boot. Somewhere else...

the car will die if screwed all the way in.
I've looked closely for cracks around the area of the screw - nothing.

as i said before, the sound is coming from the side of the throttle body, not from the screw area...

turning the screw counter clockwise increases the idle, but not enough for it to stay running.

found a vacuum leak..
no car right now to go to the store and grab a length of hose, but i'll get there tonite.. hopefully this does it..

where was the leak and how bad was it?

the one i'm holding (that you cant really see) in this pic.

http://forums.pelicanparts.com/uploa...1143152857.jpg