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I’m trying to find resistance specs for the fuel sending units. I looked online from what I can tell usually it’s 40 empty 250 full. So the front take reads that when I checked it. But does anyone know the spec on the rear tank? The guy who drives it says he runs out of gas at half tank. I checked the Blanche pump and module.the module isn’t turning on the pump. I cut the pig tail off the sending unit added 3 ft of wire to make an extension to check resistance before pulling the tank out. It reads 1.234k ohms
Had a quick look and couldn't find a spec for the sender units. P0461 flow chart gives the same 20 ohm minimum change in resistance for a 25% change in fuel level so guessing they're supposed to be the same.
That'd explain why the vehicle runs out of fuel at around "half full". The FPBM is likely averaging the correct main tank reading and the aux stuck full one.
There's probably something wrong with the balance pump too though. With the aux tank "full" it should be coming on. Could be it burned out running empty because of the bad sender?
