I drove to work this morning and after about 5 minutes driving the temp. needle went up to max in about half a second. It stayed at this for almost two minutes and then returned to normal. It did not go back up for the remainder of the journey which was approx. another 30 mins driving in both stopped traffic and free flowing traffic. I have tried the following:
1. Bled the system - I have bled the system three or four times now and at the minute only coolant comes out, no bubbles.
2. Replaced the coolant Thermostat.
3. Replaced the sensor on the water pump
4. Checked the Fan Clutch.
5. Checked the AUX fan.
6. Checked all the hoses.
7. Had the instrument cluster replaced with a new BMW supplied one.( Dead Pixels!!!)
I know the car is not overheating so I am at a loss. Could there still be an air block in the cooling system? The radiator, hoses and water pump were all replaced before I bought the car which is about 16 months ago by a BMW dealership.
Any ideas would be gratefully appreciated.....