hertfordnc

My little project 91 XLT 2wd is going pretty well, AC, power window, and the starting mystery are all fixed. Not to get the front tank working.

When i switch tanks i don't hear a fuel pump and the gauge falls to empty. Pretty sure there is fuel in the tank.

I checked the selector switch with a meter, it seems fine.

So, besides the selector, what else is common to both the pump and the gauge ?

What is the most likely culprit?

Also, this is 24 year old truck with only 68,000 miles so a lot of pre-ethanol rubber parts have never been replaced. Is that likely to be a big problem?

THanks

Chris_1

iTrader: (1)

Circuit should go relay, inertia switch, dash switch, pump/sender. If you have power getting through the dash switch, then probably somewhere between there and the pump,or the pump itself.
Look for electrical tape where someone "fixed" something - that's always a dead giveaway.

hertfordnc

The truck has low miles and very little evidence of bad maintenance.

THe wiring and hoses to the tank look unmolested. Likewise under the dash dosn't look tampered with.

However, I look up the fuse for a aux tank and there is an ampty slot- I don't mean there's no fuse but rather there is no electrical contact for a fuse.

i pulled the panel out, no stray wires no evidence anyone hacked into it.

Chris_1

iTrader: (1)

One fuse for both tanks. Read "just call me Sean"'s sticky post on obd1 codes (top of the page).
There is a diagram with green arrows all over it. That will show you how to ground the pump. If it doesn't kick when you do that you'll probably have to consider a new pump.
It could be that everything works fine and the pump is screwed. Or there may be a wiring issue right at the pump.