BMW 316i heats up very quickly?

My BMW 316i heats up ever so quickly when it is stuck in traffic and the danger light comes on. The fan is still running and the coolant is full. Please suggest what the problem might be and the possible remedy.
Imran, October 2007


done
Change the water pump

Ali, February 2008
Most likely cause is that the thermostat is stuck shut. I'd recommend getting it checked/replaced ASAP because if the car overheats you could blow the headgasket or worse, crack the engine.

SteveU, October 2007
link Click here to see other fixes for BMW 316i.