Fuel gauage not working properly

[Kryton]

Fuel gauge was reading 3/4 full, however, would randomly drop down to 1/4 over a period of 10 minutes.
Just went to "top" the fuel tank up, and out of an 82ltr tank, it took 77ltrs.
Gauge still says a touch over 3/4 and hasnt moved to full.
DTE only says 402kms.
What would i need to be looking at in regards to making the fuel gauge work correctly.
Vehicle is a 99 AU I tonner.

[4ford]

With the IGN switch at ON, open the boot and get access to the fuel quantity sender unit, on top of the fuel tank.

Now, disconnect the one wire to the said sender unit, (the one that goes to the indicator), and touch that wire to earth, anywhere nearby, probably the top of the tank will do it.

OK, with this wire touching earth, the fuel gauge should go directly to show full (full scale) and remain there in this condition.

If it doesn't, your gauge is the problem, if it does then there's a good chance your quantity sender is the problem.

If I recall correctly, the quantity sender and the in-tank fuel pump are both within the common assembly.
Which is easy to change.

Cheers,
4ford

Oops sorry, just noticed you said it is a 1-tonner, so scratch the comment re the boot, though I'm not real sure how easy the top of the tank is to access in the 1-tonner.

[Kryton]

Thanks, will have to have a look.
Hopefully it isnt too hard to reach.

[Kryton]

Any idea which is the correct wire?
I have a plug with 3 wires on mine.

[Kryton]

Havent really looked to much into this since i pulled the plug on top of th efuel sender and the car wouldnt start.
Drove it tonight and the fuel gauge worked properly, right from the start.
Was hoping it had somehow fixed itself, so when i got home, i turned the car off, waited a few seconds and restarted it only to have the gauge go back up to a bit over 3/4 like i mentioned at the start of the thread.

Is this a dodgey fuel sender or does it appear to be something else.
If i drive the car for a while, the gauge will go down to the correct level, however it will never show full.

[GK]

I'd reckon it's the sender. Your ute is displaying the symptoms like my wagon used to.

Got the sender replaced and voila! All sorted.

GK

[Kryton]

Was there anything visibly wrong with it when you pulled it?

[GK]

Originally Posted by davway

Was there anything visibly wrong with it when you pulled it?

I didn't actually do it, so I can't say.

I got it done as part of the cylinder 10 year test back in 2009.

GK

[cedric]

my ute one reads empty although the distance to empty is correct and the fuel light works, comming on when very low. thought it was the sender so bought new sender which is the whole pump unit,pump included. that did nothing ,exactly the same, so i swapped dashes with my other xr8 and it was STILL the same. so now i just look at the DTE

[Kryton]

My DTE is dependent on where the gauge is unfortunately.

[speedzter]

There was a Tech' bulletin from Ford about the fuel gauge sender in the Ute's and I think Wagon's. Mine was faulty, and when my pump died, I had the fuel sender "card" replaced as well, which fixed the problem.
It would read full, then drop to empty.

[Kryton]

Any more info about the "card"?
Is it part of the fuel pump assembly or is it something else.
Mine also does that - drops out to empty for no reason and then comes back up again.

[speedzter]

The "fuel sender card" is Ford's terminology.
It was available separately but not sure if it still is.
Try your friendly spare parts guy !