the fan's should kick in when the temp goes up. on my car for example, the temp guage is at about 10 o'clock, and doesnt go even a spec higher than that. the fans kick in regularly if its hot and im in traffic. My car's a 5 speed, with a new rad, water pump, thermostat. i changed them all last year when i did my timing belt. I used stock parts for everything.

my guess is that its your fan temp switch. I changed one on my GF's 98 civic. cost like $30 from napa and like 10 mins to install it.