what is the best or just one in general for checking for a vaccum leak? ideas please..

 

Put soapy water in a spray bottle and apply where you might think are problem areas.

 

what do i look for then? will it bubble more?

 

The messy way of checking for a vacuum leak is by running the motor and spraying carb cleaner around the intake or where you might think there is a leak. Youll know if you found one when the idle picks up for a sec. burning off the carb cleaner.

The other way is to seal off the throttle body and then hook up a vacuum gauge and pump to create a negative pressure inside the intake. Then you watch the gauge to see if the pressure increases after 5 minutes or something.

 

the LT1 only has a vacuum ports on the manifold. I would check each of them (EGR, HVAC, a few other i cant remember are on the IM). The TB has the EVAP and whatever. Check each system part by part. You need a vacuum gauge (~30 bucks) and watch guage. if the pressure drops fast then you have a leak.