Fuel Gauge Help

[KTLX]

All, put a blazer tank between the frame rails, all was working fine. Gauge is a new autometer gauge hooked into the sending unit. Gauge was working well, then suddenly went to E with a full tank of gas. I checked the connection to the gauge and traced the wire back to the sending unit. All are in good shape, including all the grounds. Any thoughts on how to test the sending unit and or the guage. Very frustrating.

[67chevemall]

unit might of stuck itself when the tank was empty. Little rust bond..
Now the float won't float up..?
$0.02

[rauto13]

I put an aluminum tank under the bed and when I got the truck back, had a half tank of gas, when I filled it up, the guage went to E, I traced everything and everything worked correctly except the guage was reading bacwards, I checked the guage by pulling the wire off the sending unit and grounding it, the guage worked correctly.

Come to find out the sending unit I bought had a few defects sent out, they would read backwards.

Did the guage ever work correctly and then just go to E?

If so, maybe a bad float, I have had two go bad with small pinholes and fill up with gas and then no more sending unit

[72freak]

You use a multi meter to check the sending unit. i just had the same problem and my NEW float was bad. Make sure the float does not have a pin hole and is sinking to the bottom!!!!

[KTLX]

All, thanks for the advice, the gauge was working properly and then went to about an 1/8 of a tank to empty. The gauge still moves when you turn the key on, just doesnt go past 1/4. Sucks, the tank has only been in a few months, and it was a real PITA to put in, so not really excited about changing the sending unit.