acsww4

Good afternoon everyone! I'm Adam. First time in the Subaru world. I took the plunge and traded in my FA5 for a 2008 WRX. It was cheap from a dealer with 91k. From the list of things that were done to the car, the PCV valve was replaced (more on that later). It ran like crap when I drove it, but I had the feeling that the dealership put 87 in it I got it running really well after a few tanks of 91. However I didn't notice it on the test drive, but when I got the car home it would plume bluish-white smoke from the exhaust after hitting max boost (boost gauge connector wasn't snapped completely together from PCV replacement so I had no idea what I was hitting). Opened up the hood and I see red intake runners... Also, the car came equipped with a COBB AP with a 91 tune noted as "2008 WRX w/ STi swap and Supporting modifications at 18psi" and a few E85 tunes up to 20psi. It has no catalytic converters. Car was tuned in Kansas City, MO at MKC.

I then took a look at the PCV system and found a pinched hose on the passenger side head going to the t-fitting where the driver side head met to route to the block. At this point, the large plumes of smoke turned into very vague plumes So I figured I would remove the TMIC to see if it had oil in it. And indeed, it had a very small amount of oil in the outlet, but the compressor had no signs of oil. At this point I reconnected the boost gauge. After driving the car at WOT, it was easy to see that the 18psi was actually only 14psi according to the boost gauge. I did some more investigating and decided to tighten down the compressor hose clamp. The car now boosts a full 18psi and I finally hear the wastegate fluttering. No more boost leaks. However, there is still a bit of deceleration oil burn.

TLDR; oil burn after hard run(s) and stock PCV system on the car.

From my limited understanding, this could be a result of a few things:

PCV system/blow-by
Turbo seals
Piston/ringland issues
valve seals

Thank you in advance!