I installed my electric fuel pressure gauge tonight. I used a the add-a-circuit fuse and connected it to the one that the radio is on. Anyway when I turned the key the gauge goes to 100 psi which I know is wrong. I wired it up just like the instructions said. Any ideas?
check your ground wire, it needs to be hooked up to the engine ground. plus make sure youre connected to a 12v power. or just to check and see if it works plug it right into the battery.