Fuel gauge issues
 

I own an '81 280zx, and it seems the fuel gauge is stuck on empty. Upon doing lots of searching, it seems quite a few guys are having this issue, though I think mine might be slightly unique. I have done some testing, and have found the following:

1. When grounding the yellow wire that connects to the fuel level sender, the gauge only climbs up to between 1/2 and 3/4 full.

2. The voltage I'm reading from the yellow wire is only at 0.28V. This seems wrong, what is it supposed to be?

3. I removed the fuel level sender/float assembly and gave it a good clean. Resistance levels vary from around 20 to more than 100, which seems okay, but it is a little jumpy.

Any input would be greatly appreciated before I dive deeper into the wiring.

Thanks alot guys!

Odd. the s130 fuel gages rarely give problems unlike the z31. Have you downloaded the fsm from xenon and checked the schematic. do you have analog or digital dash?

Hi rogerz, yes I have the FSM and wiring diagram. It's an analog gauge, no secondary gauge.

took a quick look at the fsm and couldn't find any help in the download version. I have a Haynes that has a complete circuit diagram but kinda small and I don't have the time trace out the circuit. four wires from the sender. white/blue, yellow, black, yellow blue. goes to a connector and then to the fuel gage but hard to pick out. I also dimly remember when I had the actual nissan manual that the electrical schematic was a pull out. Maybe look on line for either one of those as the download doesn't appear to have the electrical schematic unlike the z31 manual. About all I can help with on that. unless you have the complete diagram as you posted.

Fsm
 

The 81 FSM has a full color wiring diagram. At least mine does
And in the EL Electrical System section page 42 / 116 is the schematic for the combination gauges.. including the fuel gauge.:023:

Thanks alot for the replies guys, much appreciated

That's a great wiring diagram! Cheers