Happy New Year to all,

Just before Christmas I had my Mazda 6 (38-42mpg for 6 months prior to conversion) converted to LPG by a local dealer who has converted 4 previous cars for me without problems.

Since this conversion, though, the consumption of both petrol and gas is very lame, at about 21-23mpg. This applies to petrol as well.

the idling speed is high on starting from cold, and then begins to vary in rate, surging up to about 1500rpm every second, then dropping to 1000.

There is a considerable over-run when I throttle off.

Otherwise the ride is fine.

But there's no point converting to half price fuel if you then use it at twice the rate.

If anyone has any advice as to what he might have done or where we ought to be looking I'd be grateful. Sounds as if he's cocked up the engine management system, but how?

I am not knowledgable about engines, but I am very keen to see my investment bear fruit...

Apinargh