High Fuel Pressure! Gauge seems off too?

[Antbankstwo3]

Now I'm on the my fuel pressure. It has a gauge at the fuel rail. I haven't touched it till now. Before it read 40 vaccum on engine off. At idle, engine on, it shoots up to 80. When I took the vaccum off, engine on, to adjust the FPR & lower the pressure. The gauge didn't move from 80. I had to almost back the whole screw out & it only dropped to around 50. So when I screwed it back in to where it was, it only went back up to 65. Which I thought was odd???

So now I'm stuck here. I'm thinking the gauge could be bad. It does have a crack in the glass. Was gonna go to Pep Boys to see if they sell any there. But suggestions would be helpful. Also, I havnt changed the fuel filter yet. Still need to go get some pipe wrenches. So that could be it as well. I don't think the previous owner changed it in a long... time.

Other than that I can't think of anything else. Any suggestions or help is welcomed. I appreciate it. Thank you!

 

[v6turbo87]

Gauge defiantly sounds bad. You probably will not find a direct replacement for it at Pep boys but the will have a fuel pressure tester. That way you can at least get your base pressure back to about 44psi at idle with the vacuum hose off.

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[Chuck Leeper]

"Was gonna go to Pep Boys to see if they sell any there. But suggestions would be helpful."
Do yourself a favor, and buy a good gauge. I've tested MANY of the little gauges on the inj bench..
Most were off from 2 to 7/8 psi.
Being hung out on the end of the rail, getting hot, shaken, doesn't help w/ longevity, either.

As for the filter, that would cause low fp, not peg the gauge.