I understand a boost gauge should read 0 when engine is off. Mine reads about -3hg! Anyone know why its like that? Do you think i have a problem?

 

dodgy boost gauge

 

Is the one n only thing it can be?

 

yep

 

Electrical or mechanical guage? Mechanical then can only be the guage. Electrical then its possible it could be wired wrong or have a short

 

Oh right. Well it was on th car when i bought it. Im gonna guess at electrical but how will i know for sure

 

If its got a pipe in the back of it then its mechanical. It still will have wires for illumination.
If its all wires then its electrical

 

on the back of the gauge if there is a vacuum pipe its mechanical, if not its electrical, most are mechanical btw

 

beat me to it lol replied off my email link

 

Yeh mines mechanical. Theres a few wires n a pipe about half inch diameter. Need to look at wiring i guess too tho because my gauges dont illuminate. Anyways so it is mechanical..does that mean there could be a problem

 

it means your gauge is fooked