My boost guage has had a problem since the beginning.
It wont turn on when the engine starts- it takes maybe 5-10 minutes. It sticks up at 1.5 bar, then drops down. If i make a stop it will usually still work after I get in the car if it is a quick enough stop.
I have installed the grounding wire for the battery.
Another issue is that for the first few turns of the key the car just clicks at me and only attempts to engage the starter afterwards; which may have something to do with this problem.

 

My guess: bad wiring.

-Max

 

Is it a mechanical guage like an Autometer or something? If so, you might have it hooked to the wrong spot, or got a kink in the line. Could be a defective guage. Mechanical guages just read off the vacuum/boost source, like the nipple on the intake manifold. The wires on a mechanical guage are for the backlighting.

 

Could the pressure tube be getting kinked or something?