Turbo Gauge Pressure/vacuum

[DaveHardy]

Hi All
Have within the last 2 weeks fitted a boost gauge, and only noticed to day when in traffic that when on idle the gauge reads 10 psi vacum/ when i am moving goes up to 10 psi pressure (done washer mod) is this right to go into vacum on idle???

[NiftyNev]

Vacuum is usually measured in inches of mercury (in.HG). A slight vacuum at idle is normal. Throttle closing quickly will see a little more especially on the manuals.

Nev