Turbo Automatic Vacuum Questions

JDMMA70

Active Member
Dec 4, 2006
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Houston
Im wondering if this is a problem with my car. In P (Park) or N (Neutral) the vacuum is at -21mmHg when its in any gear like R (Reverse) or D (Drive) the vacuum drops to -17mmHg

Im wondering if this is common for automatics of if its there's something wrong with my car.

Thanks
~JDMMA70