FUEL FILTER LIGHT coming on and off

I have a 306 TD Nreg and amoungst all my other bloody problems i have an annoying inconsistant "water in fuel filter warning light" which keeps coming on and off on my dash board. Sometimes it stays on for a while and sometimes it appears for a few seconds and goes out. This problem has haunted me for around 6 months with no visible reprecutions. I have also had a service in the meantime and the fuel filter was changed. I have also tried to drain any excess water using the fuel filter drain pipe thingy. Still get that annoying light on and off, pain in the arse!

Can anyone help before i go insane!

Cheers

Nurd

possibly a faulty sensor then or perhaps the car has a fault code stored in its memory.