Fuel Gauge / sender problems.

[IanVFR750]

Hi All,
I currently have a fuel gauge that reads FULL all the time on my Tasmin 200. It has been like that since I bought the car but running out of fuel last week made me think it was time to get it fixed.
The Bible says problem likely to be sender wire shorted to earth but I ran a new wire from gauge to sender and gauge still shows FULL.
I'm assuming gauge is OK as needle drops to empty when ignition is off but rises to FULL again when switched back on.
The sender unit on the tank actually looks very new and shinny - it's the 2 connection one (green wire and black earth) with 6 bolts to tank. I even swapped the two wires over to see if that was the problem but still read FULL.

Are there any tests I can do to establish if the sender is at fault or is a new sender the only option.

If new sender is required can anyone tell me where to source a unit - is it specific to TVRs or is it common to other cars of that era.

Thanks - Ian.

[SEvans]

I can't remember which way round it works but taking the wire off the sender should see the gauge move fully one way then shorting it to earth should see it go fully the other way. It's relying on an earth through the metal tank so maybe don't rely on this for a test and run a wire from a known good earth to the sender wire. If doing any of this makes no difference it sounds like you have a short on the wire from the back of the gauge to the sender, or maybe in the gauge itself. At this point it's going to be a dash out job.
Regards Steve