Classic LPG problem.

Hi all, I have recently had a problem with my "Lovato" lpg system , which had been running faultlessly for the past 18 months of my ownership!There was a lack of response when accelerating hard(petrol is fine ), . Tootling along was fine , but as soon as I put my foot down , there was no response. I spoke to my friendly lpg expert ( Billy at hilton lpg in featherstone , staffs.)who told me to check the anti-backfire flap, and then try swapping the stepper motor for a manual power valve.
When I checked the anti-backfire flap it was stuck wide open ! This meant the air flow meter was vulnerable to the back-fire , so I repaired that and still had the same problem . So I then fitted a manual power valve and set it up as per his instructions.It seemed to cure my problem , but my gas consumption went right down ! Billy told me to screw the power valve in a bit at a time to achieve optimum performance , which he stated could be done properly with a co2 meter. He also stated that the sensors that control the stepper motor could be at fault rather than the stepper motor itself .Does anyone know what sensors could be at fault with this system apart from the lambda sensor (and if this was faulty , would the petrol side also play up ?).All my instructions for this set up are in italian !I believe that the coloured led's on the control unit signify the system condition.(does anyone know what they signify ?)If I fitted a new stepper motor , would I need diagnostic / software to set it up , or do I just stick it on . Any help gratefully received ! ( could it be the vapourizer playing up as it is 9 years-old).

I know nothing about LPG but I thought the leds were how full yer tanks were?

If your referring to the LED's that are in the vehicle, they are usually to show how much gas is left.... However as most LPG owners know these are usually very poor at telling you how much gas is left in the system !

T.

sorry, i meant the led's on the control unit under the bonnet (the lpg ecu).I have just found through a forum search , a link to a czech site that offers the software (free) and configuration instructions for this make of system( in english !) , and am just studying it! Apparently , I can reset the system and then let it recalibrate the stepper motor after it has learnt some parameters from the throttle position sensor and lambda sensor. Obviously , I need to somehow confirm whether my stepper motor is shot or not first. Whilst it is bypassed , I was going to plug it back in and observe if it adjusts when i rev the car.

ELPEGE | LPG | lpg-software, návody na lpg zaøízení, schéma

look there for software, you can also search fleebay for the lead!!