Just a negative update on my issue.
I was about to visit the engineer i was booked in to but then bumped into my trusted mechanic. Mentioned the LPG issue and he said if i went to this engineer he would never talk to me again as he has 5 or persons in the last year arrive at his garage with major issues after this engineer has been used.
So im in conversation with a new technician around the birmingham Tyseley area but can only do the work during the week, trying to get time off.
My Prinz system is still running fairly well but now dropped to about 19mpg from approx 22 when first bought her 15 months past.
Is this really such a specialised area of technology ?
I can guess why more cars aren't running on this fuel. Just topped her up in Derby for 47.9 pence litre.

Hi, just got back from having my LPG serviced by Blair, seems a decent guy, changed a couple of filters but could not find any real fault but suggested the injection rails my be a little clogged and may need changing if the problem continues . Car was running fine for about 5miles on the return home before the light came on yet again so no improvement. I have now had time to check my mail and read your letter and its all very frustrating as I just don't know who to trust?

Hi , are we talking about the same so called expert please,?

Hi
I had problems with my engine light coming on also, it came up with codes for running lean, it was always at low speed or stopping/setting off when the light came on. I had my ECU re-mapped by Simon at http://www.lpgc.co.uk He works from home & there are no fancy garages, but he seems to know what he is talking about & the car has been fine ever since. I would however recommend disconnecting your ECU & re-connecting as this has solved another problem I had, not sure why but it did! Always worth a try!
He was also very reasonable with his price.
Cheer's Neil

Just an update on my LPG service from Blair, the following day the car developed misfire problems on the petrol side which it had never done before, plus it had been checked by Famous Four the week before, end result I had to be brought home on a flatback recovery truck from Birmingham all 3hrs, of course its nothing to do with Blair, but I would not let him touch a car of mine again, so I continue to look for somebody who knows what they are doing where LPG concerned,Barrie

Hi again , anybody tried one of the interface kits that can be bought on auction sites, I`m thinking of trying one for my system following the nightmare I had with previous so called expert. I`m convinced mines running to lean causing the missfire, and maybe if it`s possible to confirm this and correct it ,all well and good and a lesson learned, Barrie.

You can tell if it's running lean with a cheap obd reader, check the STFT it should be no more than + or - 10%

If it was running too lean it usually puts the engine light on as the lambda will pick it up.... Pete

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2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
-Click for Project Fatty off roader-

The leads on eBay can be a problem, but most are OK, just make sure you
back up the settings to your laptop before playing, you will need the OBD reader as well
to check if it's rich or lean.... Pete

__________________________________________________
2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
-Click for Project Fatty off roader-

Hi,Pete, I have a ODB reader and will have a check, cheers Barrie.

regarding the check engine light , make sure the air intake pipe is properly fitted to the inlet manifold i had the same symptoms and found the pipe had come slightly adrift sucking in unmetered air and throwing the light on ,
remade the connection and been fine ever since  1990 3.5 v8 defender
2000 4.6 v8 30th anniversary prins lpg
2004 4.4 v8 vogue prins lpg
2011 4.4 TDV8 Vogue
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