check eng. light question

I have only owned this svx for a few weeks. I noticed that I can drive the car and then park it, come back and drive it again and the check engine light is on. I then can park it, get out do what I have to do and when I get back in and start the car the check engine light is gone. It happens the same way every time. I was just curious if anyone else had the problem before before I go throwing money at this problem