Stop in for a cup of coffee

dukeboy_318 said
It’s an aftermarket SunPro mechanical gauge. If you all think somethings up, I have a brand new Mopar performance mechanical I can swap into it and see if it changes.

If it reads zero engine off and 50 psi on the highway then seems unlikely the inbetween would be that far out of wack on a mechanical. No?

I'm thinking like Jonny said last night - maybe something with the relief spring ?