vacuum leak test

**tonyboy** · February 18th, 2009 07:16 PM

hi,
i was told to remove boot from throttle body and with engine running cover throttle body so that no air would go in, and if engine stalled off or died, i didnt have any vacuum leak. is this true?

tia

**ejaydpogi** · February 18th, 2009 07:40 PM

Originally Posted by tonyboy

hi,
i was told to remove boot from throttle body and with engine running cover throttle body so that no air would go in, and if engine stalled off or died, i didnt have any vacuum leak. is this true?

tia

no. it still has a idle vacuum leak at the intake manifold. it will still run even if you cover the tb.

**v6dreamer** · February 19th, 2009 01:13 AM

You can also check the PCV tube at the back of the intake manifold they are known to get corroded and break. The most common source is a broken plastic PCV valve.

A trick an "old mechanic" is to use a small propane torch. After you start the car, turn on the torch "WITHOUT LIGHTING" it and point torch nozzle near vacuum hoses and connections. If you have a vacuum leak the car will run normal when the torch is placed near it. If the engine idle change, Bang baby there it is.