Lift pumps and fueling

[pelky350]

New mechanical lift pump, at first my little guage would stay still for fuel pressure steady at 5psi. Now just like my old one it bounces back and forth. It's mechanical mr gasket Gage I put on my filter head. Now it's bouncing between like 4-8 psi rapidly. My truck seems to be temperamental all the time. Some days lots of power higher boost numbers other days seems to be lacking some. Is air intrusion before my lift pump maybe causing this? It doesn't act like it's sucking tons of air I know what that feels like but maybe just a small amount enough to bother my fuel system some? I may just go electric soon and see what happens after. I'm prepared with new tanks and a selector valve I'm pulling off my new parts truck. Where should I start out at? Im probably going to just replace all anyway. Rear tank has whole and neither sending units read besides full and like 1/8th tank or less either and I think my selector valve is making the return always go to my rear tank as it's leaking like I've got lots of fuel and I haven't added any.

 

[Macrobb]

It wouldn't surprise me to be air or a leak causing that pressure bouncing... how about at WOT up hill? do you see the same bouncing, or does the pressure drop a lot?

 

[pelky350]

Pressure guage Is currently just under the hood haven't got to making it mountable in the cab yet. I plan on doing that soon hopefully. Going to get a 4 pod piller and get new gauges to monitor everything better