Turbo Automatic Vacuum Questions

[JDMMA70]

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

 

[IJ.]

Watch what the rpm is doing at the time

 

[jdub]

LMAO...yeah it's common

 

[pogoism9]

yep, drop in RPM = drop in vacuum, much like IJ was hinting at