No, it will not cause any harm to drive the car with a check engine light on. If it were causing any driveability issues or if the light is flashing then I would say do not drive the car. The problem could be something as simple as a loose or incorrectly replaced fuel cap. Also, you may not need to go all the way back to where you bought it, Autozone and several of the big chain auto parts suppliers will scan the car for you and if it is a fault that says: Major leak detected, it is the gas cap just being loose and they will reset it for you if you ask nice!
Wednesday, December 24th, 2008 AT 7:19 PM