The systems seem to operate on whatever the fuel you were using before the last stop, so if you're on gas, it will start on petrol and change over to gas. if you're on petrol it will stay on petrol.
no it doesnt always, if youre switched to gas it will start on petrol then go to gas
For short trips, it can get confused, and if you are just on the change-over point when you stop, it may hang between the two, it is a microprocessor in there and responds to inputs from the engine and gas tanks etc.
again, this is possibly so on new systems but not older ones!
I'd suggest leaving on petrol for short trips, that works fine for us, but anything over 5 miles or so we switch over to gas.
you can start on gas, depending on system/switch type there are different methods. for rocker switch, switch a couple of times from petrol to gas, ending on gas and it will start on gas. for the button type press and hold the button for 5 seconds and it will start on gas. in both switches the lpg light will stay lit.
There are temperature sensors on the vapouriser that tell the gas controller if the unit is hot enough to go, if that is faulty, it may screw up your operating parameters on gas. We also have another one in one of the feed hoses to the valve blocks.
your system sound like a newer multipoint system, the gas temp and coolant temp are taken for auto change overs and should control the changeover fully for you, thats if its wired and set to do so. there are many different controllers(ecu's) and ways of setting them up.
The other known idling problem on the V8 is the MAF sensor, just changed ours this morning and makes pulling away a lot better and more reliable than before, either on petrol or gas. Prices range from ridiculous to £29 + postage, check the MAF part number before ordering, there are lots of them for the V8. We got ours on ebay, #270412080971
Peter
i know the maf isnt used on my single point system and most older systems dont use the maf.
mine is set to change over at 1600 rpm on deceleration/revs dropping. in this country you only need to start on petrol if its cold as lpg is gas at normal summer temperatures but can freeze the coolant quite easily if its not warm!
i would suggest you find out the make of the lpg ecu and get the software and cable for it, you will probably find it is leaning itself out too much/closing the actuator down too much. the remedy is to set the lower limit for the actuator during cut off!
i reckon you got a single point system? with a leonardo controller possibly???
