My car has been bucking while stopped and in gear. Eventually the problem worsened and it wouldn't turn over. I replaced the starter and the shop notified me of a misfiring cylinder. Yesterday, the bucking worsened and the "check engine"light came on. I'm currently working on replacing the vehicle, but for the time being, what level of reliability should I expect from it?
If your Check Engine Light has come on after experiencing performance issues and misfires, I would question the reliability of the vehicle for any drives longer than 20 minutes.
A Check Engine Light by itself can sometimes be an indicator of a minor issue that may not dramatically affect the reliability of the vehicle. However, a Check Engine Light accompanied by misfires and engine bucking are a sign of a more serious problem, and can be caused by a wide variety of issues. Some even with the potential to cause serious engine damage if not tended to in a timely manner.
If you are working on replacing the vehicle, I would still recommend at least having the vehicle scanned for trouble codes just to be sure that the issue is not major, and so you can get a better idea of the severity of the issue. I would recommend having a certified mechanic diagnose your Check Engine Light to find the root of the issue.