1996 BMW 318

Engine Cooling problem
1996 BMW 318 4 cyl Two Wheel Drive 187000 miles

I have a 96` 318 TI automatic, has 187k on it.
-i just replaced the coolant temp. Switch(fan switch) and the thermostat, my fan doesn`t come on and the car over heats at idle. The radiator and the hoses r LEAK FREE, the fan works when jumped, other than the high and reg. Speed relays possibly needing replacement, should I look into a water pump of would there be evidence or failure such as noise?
February 21, 2008.

Inspect and test the fan relays -computer might not be energizing it or a wiring problem from the temp. Switch

Feb 21, 2008.
There should be a fan driven off the water pump, if not it needs one as I just fought the same battle as you with the exact same car. Put a mechanical fan and fan clutch on it and you should have the problem solved mate!

Dr. Hagerty
Feb 21, 2008.
The problem was that the impeller on the water pump was detroyed due to the previous owner ONLY using straight water for coolant. There wasn`t and water flow and the water that was in the radiator never got hot enough to kick the switch. Since the switch monitors the coolant temo in the rad. It never tripped the fan. Thanks guys

Feb 22, 2008.