The check engine light has recently been lighting up on my 2001 v70 turbo wagon. this is the first winter I have had the vehicle, and I drove through a little deep snow though not much. The car got moderately stuck and I had to rock the car in reverse and drive. I have driven in winter my whole life and I did not over drive, however after starting the car the next day the check engine light was on. its very cold, and I am wondering if the cold could have something to do with it? the car also shifts weird from 3rd to 4th the first time of each trip, which developed the same time that the check engine light came on (sometimes the check engine light flashes while the car tries to shift from 3rd to 4th). is this related? is it somethign I need to have checked out?