Is it normal for the temp guage in this cold weather to start the dip slowly from the usual 90 when coasting or going down a hill, its something ive not noticed before on any of my vrs`. A lot of my driving is to work in the very early morning and late at night where the temps are barely above 0C.

The temperature gauge will fluctuate slightly as the thermostat opens and closes. This is normal. When the engine is cold the coolant circulates around the engine until it is up to around 90°C. The coolant then cannot provide cooling anymore, and has to be itself cooled. The thermostat opens and allows the coolant to pass into the top of the radiator where it's heat is given off to the outside air. As it's temperature reduces the coolant falls, and exits the radiator at the bottom, where it is returned to the engine to cool it once again.

If the engine gets too cool the thermostat closes, and the return from the radiator is closed off again. This is to regulate the engine temperature, keeping it neither too hot nor too cool, and hence the slight varying of the temperature gauge.......