S-10 Fuel Gauge

I think it may be broken.

Sorry, couldn't resist.

You may be better off replacing the entire sender unit from a boneyard than trying to troubleshoot it. Good opportunity to replace the fuel pump while you're there. $60 or so for a new pump and a boneyard sender/pickup and a full day of draining the tank, replacing everything. Isn't DIY fun? I have done this twice on my '86 S-10. For more help try the S-series.org website. Good luck. People sleep peacefully in their beds at night because rough men stand ready to do violence on their behalf......George Orwell.

Unless this is a common failure item on this vehicle, I would not assume the sender is the problem. It is only part of the system and replacing it will not help if it ain't broke. An open or short in the wiring can cause this as can a bad dash gauge. The only time I had a sender fail (been driving since 1976) was when I hit a rock on a dirt road and the wire came unplugged (saw it hanging down behind rear wheel, easy diagnosis). Plugged it back in.

If no one provides a better answer, you may need to hit the library and look for a wiring diagram. Assuming this sender is hard wired to the gauge (and not going through the computer), you should be able to unplug it and see the gauge go to full or empty. Short it or short to ground and the gauge will read the other extreme. Do this at your own risk as I cannot guarantee it will not harm this vehicle. If you do this test and it passes, then I'd change the sender as the wiring and dash gauge appear to work. If it doesn't pass, you have a bad connection or shorted wire in the harness or a bad gauge in the dash. Test the gauge next. I'd start by checking connectors.

Good luck. If it s anything like my 1996 OBDII, you cannot buy just the fuel pump or gas sender. It comes in a complete plastic module that's $200 or so.

BOB