1997 Chevy Lumina Misfire in cylinder 2

I recently had a tune up, oil change and new radiator put in the car. This week the check engine came on. I took the car to a mechanic and his computer showed "random misfire". He checked all the spark plugs and wires, and said all was fine. Another check on the computer showed "misfire in cylinder 2" so he changed the ignition coil. When I drive for an hour or so and the car gets hot, I get home park the car, and go out 30 - 60 minutes later, start the car and it seems flooded to where I have to hold my foot down on the gas pedal to clear it out. What can this be? Any help you can give me is greatly appreciated. I am totally broke right now and just can't afford to donate right now, but, I will come back to the site when I get my ss check in the beginning of the month. Thank you.