My 2001 BMW Z3 with 3.0L engine and 100,000 miles will not start. It started and ran two days ago when I moved it out of the garage and onto the driveway - about 10 yards. Now the engine will turn over but will not fire. I borrowed a diagnostic tool and plugged it into the port in the car (passenger side foot well) but all I can get is "System error" instead of any diagnostic codes.
Any suggestions would be appreciated. I've seen other similar messages on different forums but no definitve info on what may be causing this. In my experience cars don't "break" sitting idle in the driveway so I'm wondering if it may be associated with the electronic control system.

your car may have an issue with the EWS alignment.I will need more information to properly diagnose.