Is your fuel tank half empty or half full?

[cornfarmer]

So after getting some of the small issues figured out on my new to me 2.5 (2000 Endeavor), the first sorta major one has come up.

I went to give it its first (i.e. full tank) fill up. When I got it last week it had about 1/4 of a tank as indicated, so now the fuel gauge was on empty (low fuel indicator was not lit up). It only took about 9 gallons before the pump auto shut-off activated, which confused me at first with the ~24 gal. tank, so I tried pumping more in, and it puked out a little gas, as it normally would when a tank's full. YOU'LL EAT THIS GAS AND LIKE IT!

The fuel gauge then registered at only a little above half a tank. I drove it for a little bit, then went to refuel to confirm my suspicions - it only took about $1-2 worth before the auto shut-off kicked in (note that this time I didn't try to force more gas down it's throat :ylsmoke: ).

Before I go ordering parts, is this the typical symptom of a bad fuel sending unit? I found this thread below:

Replacing the fuel sending unit

 

[Swank Force One]

Subscribing. Gas gauge doesn't work at all in my 2.5, does.... things, but is hilariously inaccurate in the gen3.

 

[DSouth]

The fuel sending unit's are fairly easy to test if you have a DMM with Ohm testing ability as they are simply a variable resistor. Remove the sender, connect DMM leads then watch for the read out. Often times you can just clean the contacts and get it working again. I'd test it first before replacing. If the sender is good, I'd start looking at a break in the line between the sender and the guage, and or the guage itself.

 

[cornfarmer]

Update: I jumped the terminals on the connector and the fuel gauge went all the way up to full, so it looks like the fuel sending unit's bad as suspected. The actual contacts were clean as a whistle, so that ruled out them needing any cleaning.