Electrical fan on and off switch?

Check that your thermostat and engine coolant temperature sensor are working or replace them. You might have another issue causing a misfire, try checking for trouble codes.

I got a flashing check engine light today for about 5 seconds and then the light just went out and hasn't come back on. What is the failure rate on the fan relay because since I have owned it I've never seen it turn on

Do the coils start going bad at a certain milage because I read they can start to go bad and cause the flashing check engine light because the unburned fuel is going into the catalytic converter.

Take the car to any auto parts store, they'll read the codes for you for free. Or you can buy your own scan tool, the basic ones aren't expensive.