JGG is headed back to the shop Monday. I searched RCC "fuel pumps", "fuel gauge", "sending unit" etc. and edited together about three pages of relevant sage wisdom text for them (mostly on fixing bad ground). With brand new Bosch FP in there, a leaking float and bad sending unit should be ruled out as affecting my drifting gas gauge. I'll have them chase grounding issues, do the test to see if it pegs out at "F", check ohms, etc. If anybody can offer a nice short, presice, technical instruction for me to pass on to the technician so I don't just give him three pages of RCC search results to decipher, I'd be much obliged. I offered to loan him my '92 FSM, but he has AllData on-line, and declined. I guess he has relevant FP wiring diagrams, color codes, etc.
On just the FP noise, let me rephrase my original questions:
On a base model w/ only rubber mat, and no back seat in it, should you be able to hear the FP whirring (quietly) at idle at all?
If soft audible noise is OK, should this noise fluctuate in time with turn signals blinking or drop when brakes are applied?
Is driving with this FP ground/voltage issue going to damage this brand new (not cheap), FP?
Am I being an obsessive newb? Be honest
After new FP went in, and I filled it up, all was quiet back there for a day or two, but as the tank's gotten emptier, I could hear FP again (faintly, not loud like old one), louder once ytruck's warmed up, or it shot up to 75 degrees Wed. Of course with gauge acting like it's possessed, who knows. I think there's about half a tank in there, 'cause it's reading around 1/4. Last time it only took 14 gallons at that point. Bottom of tank skid plate is level with top of rear axle, so it's gotta be the deep 34 gallon one.