the flashing coolant light is a sign your low on coolant not dirty coolant. I would look at this first or you could find yourself stranded with an over heating engine
Well ive checked the coolant level both with the system pressurised and not; It is fine.
The coolant temperature never gets above 90C and the Oil temp is normal too.
Disconnected the coolant level sensor lead and the light stayed on; however when i shorted it and tried again it went out. Reading elsewhere on here that is suppossed to point to the sensor being dirty or knackered.