Hi guys
Okay so the story, my 2002 Volvo S 60 T5 has been burning a lot of oil for a number of years now, gets through probably a litre in 4 to 500 miles. Smokes after running down a long hill but also smokes sometimes when you put your foot down hard and I've been at a loss as to why this oil is going. Pcv is clear, Had the turbo rebuild (but I question whether it was done properly) about a year and half ago thinking it might be that but now I think it might also be the valvestem seals as the engine seems to be full of gunk and probably wasn't well looked after and its previous life. Engine has only done 95,000 miles.

Anyway I came to compression test it today to see how things looked inside and the results were Not good.
My technique may not be the best but I remove the fuel pump relay and remove the coil packs from the wires and took out the plugs, then turn the engine over five times per cylinder. First time round I forgot to keep the throttle wide open however didn't seem to make much difference when I did

The results I got basically were cylinder one abd 5 were extremely low building up to a maximum of about 90, the other three werent are bad at about 150. Putting some oil in the low cylinders picked them up by about 20 but still not much better And doing it with throttle wide-open made no difference. Either way there is A big range in the cylinders

The only thing that makes me wonder is that the car will start hot or cold within 3 to 5 cranks which is better than my 850 starts with compression of 150 all round, it Also pulls like a train and 0-60 time seems somewhere within the target value of about seven seconds. Is there anything other than piston rings that can cause low compression but halfway decent performance? I thought bad compression would lead to struggling to start and lose a lot of power?

Thanks very much in advance
Si