I have a 91 Honda Accord LX with AC, I replaced all sensors, drained, refilled and bled my cooling system. My car stays cool when I drive but once I park it and let it run for about 5 min the temp comes up. I popped my hood and I don't see the fan kicking on even when the needles is almost hitting red. Once I turn it off the radiator fan will kick on. The problem is I need it to kick on while the car is idling to keep it from overheating. What could it be?
I hear people talking about the fan relay and a timer.. Please help.

 

Start here, and have at it.

Overheating - Troubleshooting Honda's Cooling System