Detonation (Engine Knock)

WARNING: This page does not describe the selected car, but rather 37 other vehicles, including the 2004 BMW 760i, 2004 BMW 760Li, 2003 BMW Z8, 2003 BMW Z4, and 2003 BMW X5. However, it is still accessible from the selected car via links, so may be relevant.

Ignition timing too far advanced.
Blown head gasket.
Stuck thermostat (engine overheating).
Lean fuel mixture.
DME/Motronic control unit malfunction.
No coolant in radiator/engine (engine overheating).
Wrong octane fuel.