I'm not absolutely sure but when I was driving back from Moab, my check engine light came on. I knew I was about 1/2 quart low when I started out that morning. I pulled over and stayed overnight until I could call a dealership. FYI - they advised that as long as the check engine light isn't flashing, the car is still okay to drive (I didn't know this - maybe y'all did). The next morning, I checked my oil and was 1 quart low - I filled it before heading out and the check engine light went out 20 minutes later. Haven't had it come back on since but I am going to have the dealership check it out next week when I am in for something else. If it was just an oil problem, the check engine light seems to come on at 1 qt low (at least for me it did).