I have a renault espace 3.0 ltr v6 x plate.I got it converted to lpg but it is not running as it should.the car is miss firing and iam only getting 14 mpg.if i change the spark plugs its ok for a couple of miles.then it starts again.one plug is always worse than the rest.
i have an omega v6 l.p.g. & have had similar problems .
you need to get a can of carbureter cleaner remove the gas pipes from the injectors & spray inside with the cleaner reconnect pupes & start up.