Just purchased a Autometer Pro Comp Ultra-lite 30/20 boost gauge.

It's not sitting on 0 like it should off. It's not brand new, and used, time to fix it!

Before


To fix....


Remove the light bulb in the back, you will see this. "Compliments to LS1 Tech for photos below"

Once the bulb is removed you can see what looks like a copper belt wrapped along the edge of the gauge case.
This piece of copper expands and contracts.

Our goal here is to get the gauge to sit back on zero!

My Problem was I was 5 Psi under as you can see in the picture.

I used my pinky finger because I could feel the dimples I was putting into the copper tube and it fit in the light hole , but some may need to use something else such as a tool "not sharp" strong enough to put a little force behind it.

This is how this works.
When you push on the inside of the copper belt, this will raise the boost, if you fit something between the case and the copper belt "pushing toward the inside of the gauge" this will lower boost.

So if you are below Zero you will be pushing from the inside to the other part of the gauge.
If you are above zero, you will be pushing from the outerside of copper belt into the gauge.

This is how it will look if you are ABOVE 0 and want to go below.


If you are below 0 you will need to go at it from the inside pressing out. " I took this pic below, thanks Moto X"



You can see the copper tube is more like a belt, about a inch tall, you are just adding pressure to your pinky or tool to give a light dimple to the copper "in the middle of the belt" to adjust the 0.

The proper way to add pressure is to apply lightly while watching your gauge needle, once it hits 20/30 or the max the direction you are trying to fix it "Mine was toward boost" So I was watching my gauge maxing out boost at 20 but going till the needle would stop, then just a hair more and that copper will give!

REMEMBER LESS IS BETTER! You can't undo the changes! It will take 1-2 to 20 times of trying it to get the copper to dimple/depress just right. Be patient. Don't over do it, because then you will be trying to add a dimple to the other side, and that will really throw any calibration off. BE CAREFUL PLEASE TAKE YOUR TIME!

When making your adjustments be sure to shake and smack the boost gauge, as doing so will settle the needle to it's real point.

Soon you will have something like this with enough patience and diligence.


Again please take your time, I spent about an hour fiddling with mine!
** I do not claim any responsibility for any damage this fix may cause** Do at your own risk.

By creasing or bending the copper tube, you're changing its mechanical properties and it's no longer as accurate as it should be, nor will it react as quickly as it should.
I'd sooner suggest purchasing a new gauge than going forward with an "at your own risk fix" on a measurement device. If the results fall under the "close enough" clause, no modification was necessary in the first place.

I will, however, applaud the (too seldomly used) occurrence of macro focus. That feature is too often missing in detail shots nowadays.

You are correct, it's no where near perfect! I've yet to test it on a vacuum pump, but my 15 psi is right on the $ when tested against my boost leak test's gauges results. I've not tested it's accuracy any further as 15psi is all I need for the time being. I got this gauge for a steal literally a few bucks, so I would never say it's close to accurate as one of the 200$+ ones!

From the 100's of pages I read about tweaking them, one guy who works for auto meter, said they have a more specialized tool to dent the copper properly.

I've also read that I could simply call them and tell them the gauge is messed up and they will replace it free, wouldn't that be awesome, I gotta call one of these days!