You mean the hard vacuum line for the MAP sensor? If so, i have inspected it and reglued the ends and tested it, holds vacuum just fine.

 

im so lost now but maybe someone else has better knowledge then me. also check the links on my signature they might help you out

 

Just as lost as me then, thanks for trying...OH and btw no codes being thrown (i have a flashbox incase it would)

 

sorry i couldn't assist you further were both in the right direction tho

 

Its cool brother, any suggestions given will either directly solve the problem or give me the lightbulb as to what it might be

 

I have a 92 4.3 doing the same thing.. I posted a message on automotive forums dot com..
there seems to be a guy called "old master" that is quite good with chev stuff especially the older models. you might check out this place as well..

I love your video.. that exactly what mine is doing but not a good sounding..

good luck and be sure to let us know what you find on this problem
my shop guy is saying the computer may need replacing.. but the may is not enough to warrant the money.

 

Well i decided to tear apart the tbi module and rebuild it with a full kit. So far i found the fuel pressure regulator diaphram pretty bad off. Pics and results later guys.

 

Thanks for your time brother, but your right... I have pointed at the ecm as well, but not enough proof to warrant the money.

 

Here is a vid after the tbi module clean/rebuild:
YouTube - ‪4.3 vortec‬‏


Unfortunately after all that work still no change. I found alot of dirt and a damaged fuel pressure regulator diaphram but nothing more. In the vid the motor is firmly at 190 degrees and the injectors appear to be spraying fine

 

faulty computer thats my last guess that could be wrong. think about it its not trowing any codes and the truck is havein that problem