The electric fan on my 98 2.8 quattro seems to never be turned on. It was 90 degrees today and I let it sit and idle and it never kicked on. What could be the cause of this? Fan motor? Coolant Temp sensor? Fan switch? Any ideas. Thanks guys.

 

It should go on with the air conditioner. If it doesn't, most likely the fan will need to be replaced.
Remove the drivers side knee bolster (the part of the dash under the steering wheel. There is a secondary fuse box and some relays under there.

There is a big-sucker 40 amp fuse that is likely blown. If it is, replace it, turn on the AC and see if the fan goes on.

If the fan now works, it is likely that the fan is drawing too much power and the fuse will blow in a minute or two. If this happens replace the motor.

If the fuse was OK, then likely either the fan wiring or temperature sensor is not working correctly.

 

That all makes good sense. Thanks for the advice.