Gas stopped working

The unit on the drop down cover is probably a petrol assist timer, it allows the injectors to fire for a short while during starting on gas. It is what I meant by "controller". If the car remains running on petrol with the key off then that controller may be switching on the petrol system while the toggle switch is back feeding it, the EFI relay and the ignition coil. No idea how this stuff is wired as there are dozens of different ways of doing it. Your guess of the ignition switch being buggered is as good as any. Try pushing the back of the switch in with your finger. Some switches can be rescued by re-staking the metal tabs around the plastic contact plate.

Thanks for that info. I have replaced the original switch with one I have and is working ok. So that unit is a timer. I will have a look at the power to it and see if there is still power to it after the key is turned to off.
Cheers Hall