V70 BiFuel - will not run on LPG

[Mayagirrl]

Hello, I've just bought a 2002 V70 BiFuel, which will not run on LPG at all...

It's a high mileage car (253K) but came with a year's MOT. It started immediately from cold, runs smoothly, sounds good.

I promptly drove it from Burnley to London, nae bother, so I'm liking it very much, 'cos I always wanted a Volvo estate

However, even if the car is fully warm, and I'm on the motorway, when I press the button to switch from petrol to LPG, the indicator light flashes for a few seconds, then all the power dies and the car slows. Only way to continue is to press the switch again, which returns it to petrol.

I've read up on this, and whilst it sounds likely that the stepper motor is at fault, is it possible that another fault can cause this also?

I plan to keep the V70 for many years; I bought it knowing I'll have to spend some money to get it running properly

So as not to drip feed; I should mention that when filling it with petrol, it leaks massively from somewhere between the filler tube and the top of the petrol tank It drips down from above the o/s rear suspension, and I think I can see the fuel pipe up there. I'll be fixing this soonest, and I can't see how it has anything to do with the LPG problem, but thought I'd mention it.

If anyone has any thoughts; I'd love to hear them, thank you