I just bought a 1990 prelude 2.0s, my question is when I shut the car off after its gotten up to it regular temperature the electric fan stays on for at least 5 minutes or so. Is this normal?

 

The coolant temp switch is bad. My 90 accord did the same thing, as did others. It isn't an expensive part, though. What you can do is disconnect it, as many have done before you, including me. Mine has been unplugged for about 3 years now. The car wont overheat, and the fans will cycle normally.