burning alot of oil, pcv valve?

i have a 1990 GT, no engine mods. the car sat for the whole summer before i bought it and then for most of the winter in my garage. recently ive noticed smoke coming out of my exhaust when i am accelerating or downshifting and when i shift or let off the gas. it leaves grey smoke. the car burns oil very badly, i am adding a quart of oil every week at least. the car leaves NO puddles of oil on the ground and the motor is running great. what do you guys think? valve seals? a friend of mine suggested something to do with the PCV valve but idk what to look for. please help.

in 4th gear on the highway, if i put my foot down hard it puffs grey smoke, but only when i open it up hard, when i let off it stops, when the car is idling, NO SMOKE. i was thinking pcv valve letting oil into intake, burning it off?