I was wondering if anyone knew where the hose on the intake fitting that goes behind the tbi plugs into its a simple l shape fitting that of couse sucks hair it makes a whistling noise when left open or dies if pluged. having an issue where truck idels fine but dies if I try to move it from getting to much air to fuel. thought that would be good place to star.
88 jimmy full size with 5.7 tbi 4 spd standard 4x4 ill try to get pic up here asap but cant find it anywhere online

 

I have an 85 and on the fire wall is some kind of sensor that has a vacuum line from it to the manifold vacuum source. I know for me I put in vacuum diagram or parts for Chevy 305 and searched google images and found all kind of pics and explinations. I feel your pain I just replaced my carb and replaced or plugged every vacuum or rubber line in mine. I never could find the problem and it was time to replace all the lines anyway.

 

well I found the diagram as well as an old pic of it before still can seem to get it to run right. it will idle to low then try to idle up and die. if you give it gas it just bogs out and when it does idle it sounds like a whinning noise from the Throttle body egr moves and switched out the iac with a known good one

 

did you find where that line went? If not,it runs under the map sensor and plugs into a 90. Without it plugged it'll lope like it has a mad cam till you touch the throttle.

 

yea I think I have all the vacuum hoses figured out but still having issues. I have read that it might be the pump so im going to try and figure out how to read the pressure on tbi's it primes and gets a good cone spay but read it still might be low which whould make since if it is sucking in more air then fuel. im think timing might be a little off or rockers to far tighten work on that tomarrow

 

What do you mean a 90 can you give me a better discription or maybe a pic thanks the only 90 degree fitting I can think of is the one I'm trying to find where the other end goes the guy before me had it running to right side of tbi but I can't get it to run right their i moved the lines around for the hell of it and can get it to idle if I plug it into egr but won't drive which is how I'm going to try and readjust the rockers today