If the problem is there on both gas and petrol, ignore the gas side, it is a problem with the car not the gas system. Get it right on petrol and the gas should sort itself out.
You might get more response if you post in the Having Problems forum rather than this one which is intended for news about LPG.
'96 Saab 900XS, AEB Leo, sold
'93 Range Rover 4.2 LSE, Lovato LovEco, sold
'98 Ex-Police Range Rover 4.0, Singlepoint AEB Leo, my daily motor
'97 Range Rover 4.0SE, eGas multipoint, a project.....
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