Got a question, i have a 5.0 tbird with 90k miles all original, at times i get blue smoke, other times i dont. Could it most likely be leaky valve guides or could it be piston oil ring issue
Just on startup, or all the time?
If it's just when you start, probably the piston rings. That was very common back in the day. On my car with custom ported E7 heads I have valve guide blow-by pretty bad on startup, otherwise it's fine.
Have you tried any oil additives to help reduce the smoking? Sea Foam?
Another thing to check is your PCV valve. If it's old and plugged oil will get into all sorts of places it shouldn't be.
noticed yesterday, i accelerated and let go of the gas immediately which would pull the most vacuum, a cloud of blue smoke came out. got to be the valve guides.