First off, yes ive searched this a ton, and none are exactly similar to my issue, and ive tried most the the common fixes.
Vehicle: 2002 wrx, with the ej205, td04, with a full turbo back and uppipe. 111xxx miles, with all maintenance up to date, and oil changed every 3000 miles with full synthetic 5w30.
Problem: Im getting large amounts of white/blue smoke out of my exhaust. This only happens when the engine is hot--it has never happened when cold. It is coming out in a puffing manner, and the amount of smoke is directly proportional to the amount of gas i am giving it. So if i am at an idle, its lightly puffing. when i gas it, it billows and smokes alot, and then when i let the gas off it goes down to relatively light puffing, with small random heavier puffs. This has been happening for about the last 6 months, and i finally just started to try to solve it, instead of just regularly checking my oil level. I had a AP at stage 2 around the time i started noticing it, but went back to stage 1 a few weeks later.
The first thing i did was take it into a local shop and have them take a look. the mechanic there almost instantly said it was the turbo, and he recommended that i swap it for a rebuilt one from online. so i went with that, and my old turbo did have some oil in it and there was some shaft play. immediately the next day it was smoking again. so that did not work.
the Second fix was the PCV valve. When i got to it, the hose was actually disconnected from it, and everything around it was very oily and grimy, and the valve itself was stuck and full of carbon and junk. this lifted my spirits, and i figured that was the problem. so i replaced it, and put the hose back on. i instantly noticed a very low and rough idle, like the car was struggling to stay alive. after a few hours, the idle went back to normal--as did the smoking. no change.
Today i went in and did a compression check, and came up with 147, 151, 151, and 153. so my compression is pretty good.
Ive read that changing your oil to something heavier like 10 40 can stop the burning oil, but that doesnt solve my initial problem.
What else can i check, replace, or do to firgure out and solve my problem? and my other question is, depending on what the potential problem is, what might be the long term effects of said problem if left unfixed? (other than the obvious problem of running it dry and melting it.)
Any help or advice or opinions or 2 cents is appreciated. Im trying my best to avoid dropping it off at a shop and saying "fix it, i dont care how much it costs". Thanks!