My Verona has been rear ended twice, the last time by a car going 55mph, and it survived both times with minimal damage and replacement of the rear bumper.
The check engine light came on at 89,000 miles and we had a tune up and filter changes. This worked for a week and the light came back on. This time we brought it to the dealer and he blew out carbon deposits. He said if that didn't work, we should replace the catalytic converter. Well we didn't bring it back when the light came back on a few days later. I guessed, rightly, that switching to hi-test gas might work and it did after a couple of tank fulls. We tried going back to regular, then regular plus, and the light would come back on. Switching back to hi test always corrected the problem.