I have a 2002 Thomas Saf-t-liner that the fuel gauge goes to empty intermittently. I have replaced the sending unit in the tank but it still acts up for the driver. When it is in the shop it always reads correctly, go figure. Does anyone have access to a wiring schematic that I can see to check wires from the cluster to the sending unit? I am thinking its probably a problem with the gauge cluster itself but don't have any way to double check my hypothesis.
bluebirdvision what does the EF stand for, engine front? Mine is a rear engine. Are you talking about the hipop on the engine, ours do not have a lift pump that I am aware of. there are just supply, return and vent lines in the tank with a simple two wire sending unit. The wires form the sending unit run into the main harness that runs the length of the bus and I am unsure where they go form there. I know the wires are not chafed from the sending unit to where they go into the main harness.