[robertjary]

I had my 1995 Audi A6 2.0 auto converted to LPG at 105,000 miles. Changeover from petrol to LPG was set at falling revs once the engine had reached 2000 rpm, typically within 100yards from starting. When it came to oil changes, the oil from the sump was the same colour as the new oil. It ran for over 120,000 miles before the gearbox failed, without any misfiring problems and no warning lights. The running costs of a diesel with the smoothness of a petrol; best of both worlds.