Hi i have a 97 EL Fairmont with Tickford LPG and it will not start on petrol only on gas regardless of what you do with the switch. After 10mins the car will make a quick switch on its own and the LPG light will illuminate amber and then it is switchable between fuels. After it has been off for longer than 15mins same thing 10 mins before it will switch. On warmer days it happens faster. The car runs on gas fantasticlly but very hard to start in cold weather. I have run out of LPG and had a full tank of fuel but it wont start until gas has been filled up. The car feels like it runs of five cyls on petrol and we have changed all injectors fuel rail, pump and even emptied the tank,pump relay, fuel pressure regulator. Any help would be really appreciated as im over spending a fortune of time any money on this. Thanks in advance.