Need new fp gauge?

[turboaddict2]

today after i parked the car at work i went to check the fp pressure line off and it read 42 lbs. When I got home I checked it again and now it read 39 lbs. line off. I'm thinking its the gauge? It's a rail mounted gauge by the way.

 

[Mr URL]

Rail mounted gauges aren't that accurate over time. Vibration from the engine damages them.

 

[strikeeagle]

Two data points does not a study make...