when checking for any exhaust or vacuum leaks, what are the best ways to pinpoint the culprits?
I seem to remember reading about spraying an aerosol or fluid and looking for bubbles or change in idle but I want to make sure. If there is a better way I'll follow that.
I'd like to find out the cause of the slight 'bucking' I am having on cold mornings until things warm up.
thanks

 

You could up pinch off the hoses one by one where they enter the TB. If the idle goes up when you pinch off a certain hose, the leak is upstream of the pinch point of that hose.

The aerosol can idea goes like this; you spray an flammable evaporating aerosol (so the spray doesn't leave a mess) over the vacuum lines, if your idle jumps up a bit, the flammable spray found it's way into the intake via the leak.

 

use a unlit propane torch and wave it around slowly where u think a leak is. The engines vacuum will pull in the propane and make a change in the idle speed

 

wish I'd thought of that unlit propane torch idea for my truck.... if you spray the lines down, do small portions at a time, and use quick sprays. don't hose the whole thing down at once, you'll never figure out exactly where your leak might be

 

thanks guys- I will try the unlit propane torch and listen to the idle speed for changes. I'll post back if I find anything.