Erratic fuel gauge in Nissan pickup

I have a 1997 Nissan Hardbody pickup. I recently drove it from Atlanta down to Florida, the first long trip in the cold since I bought it. Shortly after leaving I noticed that my fuel gauge was going haywire (I had a full tank) – dropping down to one-quarter and then wavering above and below the halfway mark. I confirmed that I was not leaking fuel and kept going. The gauge started working more or less correctly in that it stopped wavering and showed readings that looked roughly correct, but the needle no longer drops to zero when I turn the truck off.



So my question is: can I rely on my fuel gauge at all anymore? Is this a trick of the cold? and, if the gauge does not work, can I still rely on the low fuel light to tell me I need to get gas? Thanks!

The float on the fuel pump assembly has probably broken off where it’s just being held on by the wire for the rheostat. I just replaced the fuel pump assembly in my Nissan pickup for the same problem. So you can’t rely on the gauge or the low fuel light.

And by the way, it’s much easier to tilt the box up than it is to drop the fuel tank when replacing the fuel pump assembly.

Tester