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Vacuum/boost


66yostagea
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Yes, but if you only get 18 inches, does it mean there is a leak??

:action-smiley-069::D:D

seriously though, yes it could mean you have a small vacuum leak, it could also mean your compression is slightly lower i.e worn rings. and lastly it could mean that you idle timing is retarded. to be honest i wouldn't worry about it, you'll find anything around 18-22 is considered normal. is your idle rpm stable?

Edited by QWK32
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I only get to 18. Is that bad? Does it mean a leak somewhere.

17 - 18 inHG would be idling for me. I would expect more vac on the overrun.

There could be many reasons. Cracked vac lines is an obvious one. Is your aux air valve letting in too much air? If you have a consult cable, checking the timing at idle is a good way to see if the ECU is retarding the timing to account for too much air entering at idle.

I also have a restrictor on my valve cover to manifold PCV so that may account for my higher vac number. That, and an engine in good condition *touch wood* :action-smiley-069:

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