Vn v6 after gas removal issues

[Vnv691]

Yeah was running fine on petrol i removed the rest of the system to clean up the engine bay and replace the exhaust system, as soon as I pulled the wires out of the back of the switch that switches it from gas to petrol it won't run but yeah unsure of where to check have 12v on the red wire on the injectors the fuel pump primes when the key is turned on but yeah that's about as far as it gets I've checked the loom from ecu pretty much all the way to I've injectors but can't find anything that doesn't look like factory crimps and what not , and the way the system was installed their joins were pretty dodgy I'm just stumped

[Charlescrown]

OK so you have 12 volts to the injectors. My wiring diagram shows the other wires from the injectors back to the ECU are light blue and go to ECU terminals D15 and D16. I would check that for an open circuit. Maybe it's this switch to go from gas to petrol.

['quipt4it]

Why not go back and connect the switch up again and see where that takes you

[Vnv691]

Ok no worries il check that
Yeah I can't pull it back in its completely out of the car it looked easy I was hoping to just join a wire or two back together and it be all good but yeah that's why I'm here lol

['quipt4it]

The fuel pump is only being 'energised' for a few seconds during cranking for the LPG system.
That's the reason for the 'start for 1 second then die'.
This is how it may work on your car:
There should be a Fuel Pump Isolation relay in the fuse box. It may be mounted in a spare socket.
If you lift the relay and bridge the two terminals marked 30 and 87, it would bypass the relay.
The fuel pump should operate normally. Can you take an image of the Fuse Box (engine compartment) with the lid off just to be sure.

[jxx]

reset the IAC after removing stuff from the intake and hoses?
Start and hold @ 2000 rpm for 20 seconds. (may need to press the go pedal to get it to start)