Quick one if anyone knows coz it really annoys me! I have a factory gas system on my VX and when I'm running on gas the engine light comes on, change it to petrol and after about 15 seconds it will go off, switch it to gas and maybe 20 minutes later it will be back on again. I have been told its normal but it drives me nuts!
Aparently its the Oxy sensors, because Gas is dry and petrol is wet or something when on gas it gives it a wrong reading. I was told its completly normal, the VX has done it the entire time. Code? buggered if I know lol!
That it's an O2 sensor code is a good enough description even without knowing what the code is exactly. A factory system shouldn't set a code though if it is operating the way it was designed and it doesn't matter if it's on LPG or petrol, the O2 sensor(s) will still work. (Only one of the two O2 sensors is used when on LPG). It's almost certainly caused by a fault on the mechanical side of the LPG system, it may be as simple as a tune or LPG mixture adjustment, including the ignition system (a miss caused by the ignition system will cause a lean O2 signal) or perhaps the mixer or converter needs to be cleaned/overhauled. The vacuum and vapour hoses associated with the LPG system also need to be in good condition and actually connected. The fuel control valve (the solenoid valve that controls the fuel mixture on LPG) needs to be working too. It could be the O2 sensor itself, but that it is not setting a code on petrol would tend to discount that. (you could try swapping the O2 sensors from side to side). If it's only that the light is annoying you, a piece of black electrical tape could solve it .
