is this common? I'll be idling for about 3 min and it goes off.

 

yup, that's the case on mine

 

You mean jus the radiator fan? Yeah, that's normal. When it gets cool enough it turns the fan off, and when it gets hot enough, it turns it back on. The fan turning on at idle is much more common than when you're driving down the road... especially if you're on the highway.

Matter o' fact, if your radiator fan stays on all the time, it's a bad thing. It means your engine is either running very hot all the time, or your thermostat is stuck open/gone bad and needs to be replaced. That or your coolant and cooling lines are in bad condition)

 

yup, what he said. when the car is in idle, air flow is not as good as when it's running, meaning everything gets hotter easier, so that's why the fan kicks in