fuel gauge problem

[Bailey]

I there, i know you guys n girls are the people with the know so wondered if you can help me. My car is an e30 325i convertible, and the fuel gauge doesnt seem to work. I've changed the instrument panel (clocks) to see if that was the problem, changed the actual sender unit, and changed the sender unit which activates the low fuel warning light (the little one on the fuel pump) and still no joy. Is there anything else i can change, or am i being stupid and missing something obvious? somtimes when i wiggle the two pins on the sender, the gauge goes all the way to full, and then all the way back down to empty. Also, is there any way i can check to see if the sender i bought from a breakers is working properly? Thanks in advance, Guy.
P.s its a right pain having to fill up my car all the time lol

[gazm3]

I have the same fault on my motorsport. Just had a new fuel pump fitted at the stealers. Came back with a haywire fuel gauge. I have checked the sender connections. Looks ok.

Help needed as well mate. Brian where are you?.

Cheers Gareth.

[Brianmoooore]

Simple enough circuit - a gauge in the cluster and one or two variable resistors as level sensors in the tank. Some cars just have the one sender, combined with the fuel pump, and other cars have a second level sensor under the left hand round inspection plate. In these cars, the two senders are connected in series.
If the cluster is a known good one , then the problem can only be the sender(s) or the wiring.
If the gauge moves when you move a connector, then I should check out that connector very carefully. Look for broken wires and female pins that have been stretched.