svt stall problems

I just got my car not to long ago and at first i dident have any problems. then as i was driveing and i go to stop the car just dies out and my engine light comes on......then it starts back up fine and it will run good for afew days or so and it will do it again....if u have any possible ideaswhat this might me let me know thanks alot

Air/Fuel sensor is my guess.