Hello GWB1967, I can't comment on the specific car you're looking at, but I've had no problems at all with the engine in my i6, and I'm not aware of any 'inbuilt' fault with the design. It is a Volvo engine with modifications to the lubrication system to cope with more extreme operating conditions, and is a smooth and quiet installation with a fair amount of 'get up and go' if you want it to. It certainly uses more fuel than the diesel, mine averages around the 25 to 27 miles per gallon in UK terms, but that is down to my personal choice weighed against the benefits I perceive that the petrol version has against the diesel version. The fuel gauge issue woul be, I assume, common to both types of vehicle and not a specific petrol engine failure. Is there any chance of getting an independent third party, say from the AA or RAC, to vet the car so you have an outsiders view? If they can clear up the issues for you I'm sure you would be very happy with the i6.
Good luck anyway!

if it was me I would have walked the moment that the dealer released and wiggled the steering column. If there is an intermittent electrical fault on the starting what are you going to do on a cold January night, pitch black in 12" of snow 20 miles from home when it re-occurs? Rusty discs ? nothing a few 60 mph stops will not clean Mould personally that would be my second clue to walk. There are loads of hi spec cars for sale and if it is cheap it is cheap for a reason

I would not be surprised if the fuel gauge problem has not been fixed since May, now let me see spend £500+ when I'm going to part ex it in a couple of months

You must be keen to buy the car to take it for a test drive without instruments but think with your head not your heart before you part with the cash, because it will take a long time to re-sell if you fall out of love with it 2009 GS Auto Zermatt Silver - Sold June 21 after 10 years of ownership

2016 Subaru Outback SE 2.0 diesel SE Premium Lineartronic Sold 2024 after 8 years and 80k miles . Best Car I ever owned !

2023 Toyota Hilux invincible X 2.8 Auto .

I had an i6 for a while with no problems except the fuel consumption but this one seems like trouble waiting to happen, don't do it. Gone, 2007 TD4 SE Auto Baltic blue, clear side repeaters, full sized alloy spare.

English by birth..... Yorkshire by the grace of God.

Rearrange the words "touch"; "wouldn't"; "bargepole"; "with a". Or it will end in  10MY (Sept 09) TD4 HSE Auto in Stornoway Grey (Now Gone)

08 FL2 TD4 SE Manual in Rimini Red (Now Gone)