'05 v70 n/a Surging on acceleration

[Faust]

I did again and bought another P2, this one an '05 v70 n/a, about 180k and apparently well cared for. At first performance was very power with very low power. Initially I thought this was perhaps a bad coil being similar to a condition I had with another P2, but as I add a few miles, it improves. I still have low power but most noticeable is that on acceleration it surges, losing power then regaining it. At highway speed there is also some surging but much less detectable. It seems to be improving gradually. It is possible that the car sat for some time, the service records end in 2021. I have no idea, does anyone have a suggestion? I am wondering if it sat and gas evaporated in the fuel system leaving residue.

[Krons]

I’d check codes and run a bottle of Berryman B12 through it. Oh, change fuel filter first.