12 13 Notes on checking ignition system
WARNING: This page is about a different car, the 2010 BMW X3, 2009 BMW X3, 2008 BMW X3, and 2007 BMW X3. However, it is still accessible from the selected car via links, so may be relevant.
Troubleshooting -> Fault in fuel injection system
-> Spark plug faults
-> Ignition coil faults
-> Further fault patterns with evaluation
-> Additional fault notes for troubleshooting
Oscillograms -> Normal oscillogram
-> Oscillograms of ignition coils from different manufacturers
Check -> Secondary signal for stationary ignition distribution