Hi guys I just bought a 95 tahoe with the 5.7 and it runs great except for right off of idle it has a hesatition. I just did a complete tune up and nothing changed. I even changed the TPS synsor but that didn't help. It doesnt matter it the engine is cold or warm driving or parked if you rev the motor up to about 1000 rpm or so it runs really rough and wants to stall out. I took it down to shucks and had them use one of their scanners on it but the guy there said that he could not get a response out of the ecm. The truck runs great other then that it idles just fine and still had lots of power. Also there is a smell on the out side of the truck when it is running but there doesn't seem to be any oil leaking on the exahust for that is what the smell is like. Any suggestions?

 

intake gaskets r bad about leaking on those. u might want to check that out. how many miles r on it?

 

190,000 I was thinking that it could possible be a vacum leak from the throttle body

 

that could be a possibility. get some carb cleaner and spray around ur t/b and ur vaccum lines and see if the idle changes. being that old and that many miles the hoses r prolly getting cracked and wornout.

 

I will try that also I am going to check the map synsor

 

Have you cleaned your MAF? I just had a dirty one do the same to me.