Intrepid 2000 engine light just came on

I started to look for a car for my girlfriend and for gigles looked at reviews for my Intrepid 2000 on Edmuns and freaked out.

I just got my check engine light 3000 miles ago, at iddle speeds it flickers in and out. I'm thinking may be it's the oil they put into my car last oil change. Does anybody know a way to prevent engine failure for Dodge Intrepids mine only has 48000 miles. No wonder I'm the 3rd owner of this car, I'm almost ready to sell it myself. Should have done more research on the car.

Let me know of any preventative maint. I can do, oil, dealership, etc.

Thanks
William