Jaguar Repair: Hess & Eisnhardt XJS..V12 1897 Fuel system, charcoal canister, fuel injection systems

Question
Howard I will try what you recommended, you asked for the VIN for fuel system clarifiacation.SAJNV584OHC136684, seems so complicated ...can the system be modified to a simple fuel cell, appropriate pump, vent and fuel line plumbed to the rails??  The original question concerned stalling & the system in general and what my configuration is.  I definitely get the big whoooooosh when opening the fuel cap.

Thank you

Answer
Hi Lee,
Sorry Lee, fuel injection systems are complex and not simple. While symptoms some times lead a mechanic in a direction, the symptoms are usually useless in diagnosis. Testing is the only method to arrive at a solution. The wiring diagram is a useful tool in diagnosis of any injection system. A wiring diagram is just a road map of electrics. Just follow the circuit that affects the section you are needing (fuel pump circuit in your case) The letters next to the wires are the colors of the wires and the numbers/letters next to the relay pins are the pin IDs. Each relay shows it's internal operation so you can see how it operates and what it does. If this is too overwhelming for you, you should be able to hand this to a mechanic and they should be able to diagnosis an electrical problem with the fuel pump circuit.
As for the air pressure in the tank, all Jaguars maintain air pressure in the tank or tanks on some Jags. The venting of the tank is done through a pressure valve to a charcoal canister. Usually about 2 to 3 PSI. This will have nothing to do with the performance of the car.

Go to my web site and you can copy the diagram of your system.
http://mg-tri-jag.net/EFIXJS11x1.jpg
Howard