Ignition System
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2006 Jaguar XKR, 2006 Jaguar XK8, 2005 Jaguar XKR, 2005 Jaguar XK8, and 2004 Jaguar XKR. However, it is still accessible from the selected car via links, so may be relevant.
The 14mm spark plugs, one per cylinder, locate in recesses along the center-line of each cylinder head. The on-plug ignition coils are secured to the valve covers.