Instrumentation and LPG
 

Do regular OBD-II based computers work well with LPG? I have seen several users reporting that SG and some others do work, but can I assume that whatever computer I'll buy, it will show my fuel consumption correctly?

ADDED:
Sorry, wrong forum. Moderators, please move it.

I have found the answer to my question.
It is: no, they don't show it correctly. Engine management is tricked to think it runs on gas and shows amount of gasoline it thinks it burns. According to the company that installed LPG for me, real consumption is from 0 to 30% larger.

But once you calibrate it to your car and driving, I see no reason why it shouldn't be accurate. After all, the AFR on a petrol engine running LPG still remains more or less constant.

Indeed you are correct. I use a Scangauge, on fill-ups. Just adjust what the computer thinks the volume of gas was to what it actually was using the + and - settings.
There are, if you want a very high degree of accuracy, some problems. My car switches over to LPG after about 1 mile. The Scangauge cant separate the difference between the fuels so the net result is a slightly miss-leading higher LPG MPG. This adds up to about one gallon of petrol consumed for every 6 weeks, and I can live this this.
Whilst setting the computer, don't forget to adjust it to true speed, which on my car was about 1.5% out, as this is effecting the overall mileage trip.
Lastly, the tank fill-up seems to vary from the estimated LPG remaining- I put this down to the cut-off valve is operating in slightly different positions. One fill gives good MPG, next time poor, but overall the tank fills will average out. This is one reason why I started the trip log on this site.