I just bought my 08' Aveo 2 weeks ago. Last Thursday I start up and leave to get my spare key from the dealer. The check engine light comes on and the car doesn't go past 15 mph, even if i put the pedal to the floor. I park, pop the hood, and see steam coming from the radiator. I cant find any leak, and the coolant reservoir is full to the top and steaming as well. I try to start up again, but this time it takes three tries before it starts up, and there is puttering like it does not want to start. While in idle, the car is revving itself without me touching the gas pedal. I have no warranty and no clue of the problem. Can anyone help me figure out what it wrong?