How to check for vacuum leak?
10-27-2015, 07:45 AM
#1
Racer
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How to check for vacuum leak?
I have an 05 base coupe m6 and have a problem with the rpm's rising every time between shifts. It is worse when cold. If I disconnect the battery it is good for awhile. I am thinking I have a vacuum leak or at least want to check for one before I go further. I bought a smoke vacuum leak machine. I was thinking to seal the throttle body and send the smoke in the brake booster hose and see what happens. What do you think?
10-27-2015, 07:50 AM
#2
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St. Jude Donor '15
Supercharged or no?
I'd try smoke and you can add some compressed air too through the brake booster hose. I've used soapy water to spray all over everything they could leak before too (along with compressed air). Worked fine
Stock tune?
I'd try smoke and you can add some compressed air too through the brake booster hose. I've used soapy water to spray all over everything they could leak before too (along with compressed air). Worked fine
Stock tune?
10-27-2015, 08:37 PM
#3
Hook up a vacuum gauge and see what your reading is. A vacuum leak will read low or show fluctuation. You can also get a a propane torch and gently spray it around the manifold and vacuum lines and watch the RPM. Check the easy stuff first.