I have my suspicions that my XF isn't running to good on gas. Most of the time I'll get about 400km to the tank which is 65 litres. The car hasn't been properly tuned since I got it in 2012, My Dad and I did adjust the fuel mixture a bit, but that didn't help. It's auto, dual fuel, Impco 300A Mixer with a 'LPG spares' B2 converter. Car is as stock as stock can be, still has the date of manufacture stickers on the seatbelts. I don't drive it hard (it's a grandpa car so I drive it accordingly), and most of the time is spent on the highway, no city driving. Would it be worth taking it Lakeside Automotive in Reservoir (where I got the gas installed) and they can tune it? Could this be something I could fix up by tweaking with the mixtures?
I've recently filled up at Supagas, and it may just be a placebo effect but the car seems to run better with a marginal increase in fuel economy.