[M491Cabriolet]

As it turns out, there is nothing wrong with the engine. I guess it just sat for too long. The cylinder I thought was dead has come back to life and the car runs fine. There must have been a bit of carbon stuck in the valve or something like that. Actually, I am still having an MFI tuning issue--the car runs really rough only when it warms up. That is something I know I can handle, with patience. I'm just glad I won't have to tear the engine apart!