Sounds like air lock, have you checked how much water you have in ?
yep all levels are ok! i think the garage i brought the car from may have topped everything up before i got the car so it may have happened then! anyone have any ideas how to clear it???
When the car is cold, start it up, take the rad cap off, put the heater on full/hot, when car/water gets hot, see if you can squeeze/pump any of the water pipes with your hand (keeping a look out for any belts, dont put you hand near then) to try and get any air out of the system, sometimes parking your car on a steep hill will do the same, sort of getting the air to the top. I dont know if the altezza has a point on the cooling system that you can bleed it also.
excellent! ill give it a bash over the weekend
thanks very much