I know ive seen this before but my searches have not turned anything up ??? I'm thinking I have A leak at idle while in gear my vac is 12-14 in. Hg. When I put it in park I go up to 17-20 in. Hg. Also idle is very rough but never stalls. any one else have these issues ??

 

you can spray a little bit of starting fluid at your hoses till you hear the idle climb. spray one line at a time

 

Doesn't that make a big mess and create a fire hazard ???

 

the majority of it will evaporate very quickly leaving very little if any mess really. Ive used this methor numerous times with no issue of mess and no fires. Your not looking to douse the hose just a light spray on the hose and the ends to find a leak.

 

I always pressurize the system to find my boost leaks. The carberator cleaner/starting fluid seldom works for the small or intermittent ones. Its a little more complicated though. cap off the exhaust and intake and run an air line w/a pressure regulator into the intake anywhere. Make sure you don't put more than 5 to 10 psi in or you'll start blowing seals and gaskets. Then spray everything with soapy water and look for the bubbles. guaranteed to find even the little ones. some garages can fogg for them too but I don't let other people work on my junk.

 

Small bottle of propane sprayed around the hoses works well too, less mess than starting fluid.