The computer is located behind the panel to the right of the passengers feet. It's not easy to test, but I know one , and good, way of testing it when there are startingproblems: Remove the entire relay/fusebox, DO NOT disconnect any cables, turn the box upsidedown and locate the fuelpumprelaysocket. Locate connection #2. There is a yellow-black cable. Make a jumper from that to earth, and try to start the engine. If the relay turns on, and the engine starts, there is probably a computerproblem. It happens. The metod above is only in effect with original fuelconnection, and no LPG. In your case the cables between the relay and the computer COULD be broken by LPG- relays. I suggest you talk to your local dealer, and get a wireingdiagram. It's much easier to work with one. Finally I will warn you to use other than original connection in cases like this. In other words: No homemade connection with own relays. It could be very dangerous, as the system is constructed to cut off the pump when engine stops. The pump should NOT keep running in case of an accident, and i
gnition still on.

Good luck