Hi,

 

My boost gauge sits on about 3/4 (or even 2/3) of the way in negative boost when idling, but all the way to -14 psi when I come off the gas when the car is moving.

 

Should the gauge stay all the way over to -14 psi when idling? My revs are nice and stable on about 650 rpm. If so, is it an indication of possible problems with piston rings? I thought I read that somewhere.

 

Bart

Maybe a boost leak somewhere. Thats what was wrong with mine when the vacuum on my boost guage was doing this. Check all your hoses in the engine bay.

 

Justin

This is normal in winter,allways more negative vacuum in warmer/summer months,you will find that when the outside temp increases next few weeks the gauge will fall back more to -14, all down to air density i think(sure some one on here will elaborate more),unless of course the Z you have has allways been this way then you may have prob,my Z is same,and previous Zs owned have done simlar

 

Tony :)

Sounds normal to me, if you close the throttle with a higher engine speed it will generate more vacuum. You would have to have a very serious compression problem for it to be causing poor vacuum, much more likely to be a vacuum line somewhere in the intake system leaking. However 3/4 the way over the stock gauge at idle is normal.

leaking pipes will be found by 14 of psi faster than negative vacume so iff its boosting to 14 it wont be a leak :)