[NacsMXer]

Originally Posted by Crash!

Is the needle at 10 PSI engine off? If it is, then you would see 10 units off normal under all conditions. That is if the guage works but is out of calibration. In the example above, if you expect to see 17-20" vacuum at ldle (you should), then the guage in the image above would peg negative (vacuum) at idle. Then under WOT it would show 0-1 PSI under boost if you have a connection to a MANIFOLD source, because the needle is already 10 units off.

I would consider that guage to be faulty. You can get a cheap vacuum guage at a parts store. You can use it to verify the MANIFOLD vacuum port you connect the guage to and to verify the accuracy of the Autometer guage. I would replace the guage it if the needle does not rest inside the "0" square on the face of the guage.

I agree with Crash!...from the looks of that pic, that boost gauge is definitely way off. I had an Autometer Lunar series boost gauge that used to sit at 5" vacuum when the truck was off. I always thought it was normal until I noticed I was getting low boost at WOT. I called up Autometer and they said it's definitely supposed to sit in the "0" box when the vehicle is off. Caused my boost reading to be about 5 psi lower as a result. Got a new boost gauge from Autometer, it sits in the "0" box, and all is well. Call up Autometer and tell them what the gauge is doing...they have excellent customer service and should replace it free of charge