No Heating in 1997 540I
I got this major problem. The car is a 1997 540I and there is no heat at all when the car is at idle. This is killing me. However, when I rev the car up to 1500 rpm while standing still, I start to get some heat out of the vents. If I don't rev the car while waiting at a red light, the blowing air is dead Cold ... Once I am driving the car, the heat is back. No problem on highways...
Can this be the Water pump going weak ? The belt that drive the pump have been replaced not long ago.