Fuel gauge...Very Odd!

[Fricfrac]

Filled the 4 runner up Sunday morning, drove about 15 miles and noticed the gauge reading under half. Oh fqsticks I think, holed the tank or has a pressurised pipe come adrift. Any way, stops in the middle of a wood, car on tickover, fuel gauge rises????

Drive away, gauge drops. So parks the lump up overnight, drives away Monday, everything hunky dory. Must be a self mending problems I hoped. Nope ,same thing today, when driving the gauge drops to 1/4, no low fuel lights show, just the gauge seems random in what it indicates.

Any ideas?

[BUSHWHACKER]

Could be:
Loose connection on rear of dash clocks.
Faulty gauge.
Faulty sender in the tank.
Faulty voltage regulator on the alternator.

Nearly all the tanks that I have removed in the past have had badly corroded connections on the sender unit, probably due to it being at the front of the tank and gets wet easily.

[Fricfrac]

Thanks bud, i`ll take a look at the things you mention.

[Fricfrac]

Just checked the easiest access first, the alternator. Put tester on the both batteries ,both read 12.5 volt. Fired engine up, both read 12.5 volt. I always understood that they should read 14ish volts with a good alternator, is that correct? If so, have I found the problem straight away?

Many thanks.