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21 Posts
Discussion Starter · #1 ·
Oil smoke..

smokes at Idle after driving..
Smokes in between shifts..
Does not smoke while cruising..
Does not smoke under power or at WOT..

Runs amazing, makes boost great, compression test is good, doesn’t seem to have excessive blowby..

It’s probably the turbo and I should start checking the boost pipes and down pipe for oil I imagine..

It has a VF48 and has anti lag/2 step rev limiter..
AND it seems like the FORGE bypass valve isn’t working or is set way too tight because it has a TON of comp surge between shifts or even letting off the throttle from light cruising..

Sounds like conditions extremely hard on a turbo to me..

Are these sounding like typical smoke symptoms of a failing turbo?

21 Posts
Discussion Starter · #2 ·
Car had a WB when I bought it (just bought it with this preexisting issue) but the WB was stuck at 14.5-14.7 which made no sense..
I had a spare LSU4.9 lying around so slapped that in and WB works great now.. Ols O2 sounded like a broken lightbulb, something shaking around in it..
Drops to low 10s on boost safely, I can tell its running closed loop at idle and cruise and its doing well chasing high 14s, and is running overrun fuel cut I can tell..

Car is Speed density tuned by "accelerated kontrol dynamics" which looks like a good shop and so far their tune seems nice..
Seems to run about 15psi in 1-3 and closer to 18 in 4th.. Very shaky boost gauge, no restrictor.. Has some 3 port EBC on it..
Antilag/launch control makes 10psi @ 4500..

Old O2 was dry so I'm assuming not smoke/leak from turbine side of turbo..
Bet it was destroyed by the antilag..

Pulled the IC off the TB and their was some oil there, enough to form a drip..

Pulled the head breather hoses off and pointed them at fender well/battery and boosted on it.. Nothing spitting out of them.. Not blowby?

I'm thinking its the cold side of the turbo leaking oil..

Went for a few boost pulls today in it, no smoke today, and I think I noticed no ore very much less compressor surge sounds today and much more recirc BPV noise..
Wonder if the BPV was sticking and could that cause the turbo to smoke from it surging? But then not smoke when it isn't experiencing surging?

Have a Cobb 50/50 XLE BPV I might test on it to see what that does.. The Forge BPV on it now is 100% BPV no atmo..
It's running fuel cut overrun and speed density (no maf) so BOV to atmo shouldn't matter at all..

Dang this car is fricken SWEETTT!!!
It runs so good and drives so good and has LEDs everywhere and, alu rad, ARP sticker, Perrin sticker, Exedy racing clutch sticker (I readjusted pedal today and is much much better, they had it so low it wasn't disengaging all the way), grimspeed sticker, sili rad and intake hoses, 08 STI intercooler (need rubber bellow from hood), STI blue injectors, new trans, depowered steering..

I have no idea what all is on this car but it seems nice.. Body is quite nice, interior is very nice..
Guy I bought it from had it a month and got scared of it (mechanically) I believe..

I should log it a few times and see if the ECU/tune is locked or open, but I'm so darn busy..

Bit smokey.. Really thinking its the turbo..
Maybe just caused by that really bad compressor surge?
IDK yet..

21 Posts
Discussion Starter · #3 ·

I kinda just discovered it did this while revving it, lol..
See, it doesn't smoke at all there.. Well, the black is the fuel for the antilag, but no blue..

What are these tail lights BTW?
Seems they cut the rear bumper a bit to fit them..

21 Posts
Discussion Starter · #4 ·
Spoke with the tuning shop today and got a bit of history on the car..

Guy that owned it who went to the tuning shop spun a beating in the engine, replaced engine, sold car..

Next owner blew the trans, replaced it, sold car..

Guy I bought it from, noticed it smoke a bit, sold it to me..

Now it’s mine..

Turbo is super tight like zero shaft play radially or axially..

Drip of oil by the TB but nothing to speak of in the Y pipe..

I think I’m going to have to get it to smoke again and shut it down while it’s smoking to figure out where it is coming from..

It hasn’t smoked at all the last few times I’ve ran it, even getting it hot and boosting..


Think I’m gonna have to kill it while it’s smoking like a plug chop to find it before it clears itself out again..

Where the heck is everyone around here?

Kinda lame.. Nobody likes to chat?

21 Posts
Discussion Starter · #6 ·
Decent bit of oil in the crank breather hose to the PCV valve..

Working on venting all the head/block breathers into a jug and blocking all their intake ports..

And then test drives..

Smoking only under vacuum could very well be sucking crap from the PCV valve..

21 Posts
Discussion Starter · #7 ·
Bunch of boost pulls with all crankcase vents to a bottle..
No oil whatsoever in the bottle..
Light misty smoke in there..
Looks very healthy there..

no change in exhaust smoke..

But the turbo feels so tight!
The bearing feel like brand new!

I also took the forge BPV off of it and put on a Cobb XLE BPV venting 50/50 to atmosphere..
This completely got rid of the terrible turbo surging noises at lift when it should have been blowing off..

I even strip cleaned the Forge and it didn’t change anything.. Maybe it justhas an incredibly stiff spring in it?
XLE BPV seems better to me..

I bought a turbo rebuild kit for it, but I really just don’t want to do all that work pulling the turbo..
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