Zx Fuel Gauge Telling Lies

[razorrobo]

I have a ZX 1.9td estate, this car is great apart from the fuel gauge. it stays at half way for ages some times, shows it's full up sometimes, shows empty some times and just seems to go up and down depending on how it feels, have run out of fuel twice now and its getting a bit annoying now.

 

Looks like the float/ sender is accessed under the rear seats, is this likely to be a sticking float or some electrical problem/ Also is it easy to remove? looks like the unit is screwed onto the tank but cant seem to unscrew it.

 

Is this a common problem, (it's p reg)

 

Thanks