Ian Kelsall on Facebook Says The vehicle does not have a factory fitted alarm or immobilizer but it may be fitted with an aftermarket system which could disconnect the fuel pump. Look around the wiring under the dash panels looking for none standard wiring. The fuel pump should run for 2 sec’s when the ignition is switched on so disconnect your wiring bridge, get somebody to turn on the ignition on as you check the pump in the boot. If the pump runs then this confirms the engine management is powered up and getting an ignition feed. If not then check the inertia switch on the passenger side door frame. If the Fuel pump runs for 2 sec’s but does not run when the engine is been cranked then check to see if the ignition amp on the near side inlet manifold is sending a speed signal to the fuel injection control unit and switch the ignition coil to supply the spark. You could replace the engine with a V8 but I feel that the V12 is more in keeping with the vehicle which you have. On behalf of XJK Jaguar Specialists LTD Ian Kelsall www.xjkltd.co.uk