[Kiwibilt]

Aloha,
Im trying to bypass the fuel switching valve to determine whether or not the float on my sender unit has sunk, causing my fuel gauge to read empty all the time. My 87 F150 has a 6 port valve & has no wiring connected to it ?. I think it is the float as it read empty until I filled the rear tank...it then read full for a while, and now reads empty again.
The tank selector switch functions correctly as I can disconnect the front pump, & hear both in tank pumps run briefly when I toggle the switch.
Are these valves wired, or should I just check the senders ohm output ?.
Mahalo

 

[Mr Mac]

First, welcome to the forum.

Second, have you visually inspected the wiring to the fuel sending unit at the tank? From what you wrote it sounds more like an intermittent wiring issue and loose wiring/connectors can cause this kind of erratic fuel reading.

If the wiring is good then I'd suspect the sending unit itself is bad.

Mac