LB7: Think Im in Limp Mode

MolonLabe420

DirtyMax
Apr 6, 2018
80
0
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SE PA
So I finally had the chance to work on the truck the other day... I pulled off every single ground wire I could find and cleaned them up so everything has good contact, I even made a few jumpers all over the truck for extra piece of mind. I also completely rewired the lift pump with brand new 12gauge power/ground wires with a 30a switch and a 30a in-line fuse.
The lift pump hasn't given me a single hesitation since then and the engine is running great, no issues..... EXCEPT, now while driving (with a full tank of fuel) I noticed the fuel gauge diving down to E with the light coming on and then going back up to where it should be. I haven't been able to establish a pattern such as only doing it when I turn left or turn right or hit bumps, or on a hill.... it does it sporadically and even while the truck is sitting on level ground at a redlight. I haven't noticed any changes in fuel pressure at the rail while driving or at idle or on the gauge I put in the fuel line right after the lift pump and water separator, that reads a steady 10psi constantly.
Before I cleaned the grounds and rewired everything, ALL my gauges would go wacky as soon as I hit the lift pump switch.... now its just the fuel gauge. I'm thinking the sending unit is going bad. Does anybody have any thoughts on that??