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Hey guys,

I have had another issue crop up with my car, originally it had MASSIVE blow by, but since the fit ment of a catch can, the intake pipes appear clean and dry now.

But I still have an issue, if I run up on 5+ PSi of boost, car starts blowing blue smoke, and then when I back off puts huge plumes of smoke out the back.

I noticed late this afternoon it put a touch of blue smoke out whilst idling for minute... Only seen it do it once though...

Now I'm thinking it is either a turbo oil seal, or a valve stem seal.

I'm going to pull the turbo this Saturday/Sunday and check it all out, but how can I "test" the valve stem seals?

That and what else could it possibly be?

For extra information, PCV is disconnected and blocked. Only rocker cover breathers is from cam covers to catch can, back to intake.

Car is an RB25/30DET with a bit of a mixer turbo on there high mounted.

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mine was/is doing the same thing (too much oil to the ball bearing turbo) and i have put a much smaller restrictor in so far i have not gotten any plumes of smoke. before it would start pouring smoke out the exhaust like a smoke screen if you took it above 5000rpm and then as you backed off and came to a stop it would spew oil smoke for another 30 seconds or so as all the oil burnt off in the exhaust before going back to normal (which hopefully means it didnt blow the seals on the turbo)

if it is the valve stem seals it shouldnt be occuring while on boost only the over run/idle/cruise as thats when there is vacume to suck the oil past the seals.

I had same issue with my R33. did comp test come up with 2nd cyc 145 and rest around 120ish. Turned out that I had only one good piston and the rest are with broken ring lanes.

Or check your turbo for shaft play, If it has no play and spins free then it is good.

hey mate,

my money is on the blocked PCV if not the turbo. re-connect it and see if it helps.

as stated, VSS will cause you to smoke up on deceleration as well as after idling for a while then taking off. your problem sounds similar to dodgy VSS but the smoking as soon as there is +ve pressure makes me think PCV. either way its cheaper to check the PCV than it is to check the VSS =]

Hey Security,

Trying to figure out how the PCV could be at fault.

It's completely removed, and those air lines blocked.

I'm just trying to see how blocking it would cause oil to go into the combustion chamber? As if it were unblocked, when on boost, the PCV blocks it self (If it's working) and when unblocked it sucks the oil from the head into the combustion chamber... So removing it should stop oil being sucked in on decel (And it'll be pulled into the catch can)

Or am I missing something?

It did smoke as I went to take off at friends place after idling for like 2 minutes... So... Not a good look... How can I test VSS?

Edit: Forgot to add, comp came back at 152 +/- 5 PSi across all cylinders.

My lines to the catch can got twisted around when I was cleaning the engine bay, it blew 4 lts of oil through my turbo and then popped out my dip stick, as Security said check your lines.

Mark

Or you could just have a 007 like smoke screen, I sha t myself when I looked in the rear view after gassing it for 200 meters and the street and surrounding buildings were hidden in white smoke, Wonder how my cat is now that I think of it.

like i said mate, its cheaper to just check the PCV rather than think of how its not causing the problem - i did the same thing and it cost me a bottle of oil.

it might not even be the PCV but i know a few people who have had the same issue.

like i said mate, its cheaper to just check the PCV rather than think of how its not causing the problem - i did the same thing and it cost me a bottle of oil.

it might not even be the PCV but i know a few people who have had the same issue.

I'll grab some spare line and reconnect it all up then. See how it goes...

Will le tyou all know,

Cheers for the suggestions

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