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RB25DET R33 Skyline

Few months back I got a new PFC, installed it into my car and got the car Dyno Tuned. I told them to change the Oil and noticed they used oil only worth $25 (I normally use Shell Helix Ultra $50 a bottle)

Anyway we got 285rwhp at 16psi boost (turbo is a VL turbo with t4 front wheel so the turbo could handle it) car went really good for 2 days then I noticed one day when hammering it was blowing shitloads of white smoke in my trail. When i got home the car was running on 5 cyl. Took it back to the dyno place and they fixed it by replaceing spark plugs and told me my turbo was stuffed and to rebuild it because they floored it in nutrel and it blew a massive cloud of white smoke.

It was blowing CLOUDS of white smoke which has a really slight blue tinge to it, I decided to compression test #4 and a few others so i took off the intake pipe and noticed there was a stream of oil in it and compression tested 3 4 5 which all had 150 compression.

So I took the turbo off and rebuilt it with new seals and put it back on and the smoke did not change at all. Turned the boost back down and drove it a while and it settled down a little but still blows lots of smoke.

I then took the pipe off the intercooler when i sold my turbo to upgrade to a to4e and in the intercooler there was oil sitting in there even 3 months after I took the pipe off. I took the intercooler out and turned it upside down and a stream of oil started to come out so i cleaned it with degreaser and petrol and put it back in.

Whats wrong with my car? is the engine stuffed? my rings stuffed??? the engine has done 180,000ks but never had this problem since the oil change and duno tune. The smoke was even puffing out at idle.

Would a good oil change and a oil catch can fix my problem???

Help me out!! I miss driving my line.. its been nearly 5 months!!!

As Joel suggested, get a compression test done. Heaps of smoke is a symptom often associated with smashed ringlands.

Even if your compression rings are ok, it is possible that your oil rings are rooted. It just doesnt sound right that you have so much blow by. A catch can may hide the cause, and cover up the symptoms, but seriously, you are risking doing more damage.

If you only had it on the dyno and it happened the next day - I would be asking questions of whoever tuned your car, it just shouldnt be doing what you describe unless its seriously rooted - sorry to say.

When under boost, the gasses from the crankcase get circulated into the turbo intake pipe, via the rocker cover, called crank case ventilation.

It is necessary to stop your crankcase pressurising, and the gasses must be burnt through the cylinders to comply with emissions requirements.

the gasses get into the crankcase as part of the combustion process. Its called blow by, and is gasses escaping past the rings and into the crankcase.

If your rings are shot, you will be getting alot more blow by, which suspends oil in it, then passes that to the turbo inlet. From there it gets circulated through the entire intake system when under boost (when off boost the gasses are circulated directly to the plenum, via the vacuum in the plenum, but a one way valve, the Positive Crankcase Ventilation (PCV) Valve shuts when the plenum is pressurised to prevent boost leak, thus the gasses have to go out another way.

Another test for bad rings is to take the oil filler cap off, or pull he PCV valve - if you feel air being forced out, even at idle, you have got problems. Unfortuneately this isnt 100% likely to show up problems, as if its just the oil rings and not the compression rings it may not 'breathe' very much.

have you checked the pipe from the AFM to the turbo? This is where the blow by is fed under boost, and most likely it will be full of oil too.

When under boost, the gasses from the crankcase get circulated into the turbo intake pipe, via the rocker cover, called crank case ventilation.  

It is necessary to stop your crankcase pressurising, and the gasses must be burnt through the cylinders to comply with emissions requirements.

the gasses get into the crankcase as part of the combustion process.  Its called blow by, and is gasses escaping past the rings and into the crankcase.

If your rings are shot, you will be getting alot more blow by, which suspends oil in it, then passes that to the turbo inlet.  From there it gets circulated through the entire intake system when under boost (when off boost the gasses are circulated directly to the plenum, via the vacuum in the plenum, but a one way valve, the Positive Crankcase Ventilation (PCV) Valve shuts when the plenum is pressurised to prevent boost leak, thus the gasses have to go out another way.

Another test for bad rings is to take the oil filler cap off, or pull he PCV valve - if you feel air being forced out, even at idle, you have got problems.  Unfortuneately this isnt 100% likely to show up problems, as if its just the oil rings and not the compression rings it may not 'breathe' very much.

have you checked the pipe from the AFM to the turbo?  This is where the blow by is fed under boost, and most likely it will be full of oil too.

I did check it, and it was greasy.. 200km before i checked it i ran a pipe from the tappet cover breather to the road so no more oil would go into the intake (if thats where it was comming from)

Why did you stand by and let them put cheap oil in your car??

How often do you check the oil level and was it ever too high...eg...overfilled??

Have you checked the oil pressure??

Have you compression checked the other 3 cylenders yet??

This probably has nothing to do with the tuner. Worn rings dont happen in one dyno session. As he said its done 180,000kms.

Michael...

what about smashed ringlands, does that only happen after xxxxxx kms. Read back a bit, car tuned, 2 days good then lots of smoke, hmm, either bad tune, bad fuel, too hot, could be alot of things - but in my experience (be it limited) a good tune is not going to smash ringlands unless there is something else happening, and a good tune should be able to protect the car somewhat from the driver.

Well if you have disconnected it, and cleaned the cooler andpipework, you wont get any more oil on the intake side, unless its via the turbo, which as I believe is very unlikely.

Leads us right back to your rings.

The only thing that i cleaned at that stage was the pipe that the blow off valve is on, and it allways had a stream of oil in it every time i pulled it off (5 or so times)

I only just cleaned the intercooler last weekend and noticed it was oily, when tipped over to one side in about 5 seconds oil started pouring out of it.

Also when the intercooler was in the car before i cleaned it the outlet pipe of the intercooler still had oil on it (put my finger in it and scouped up a bit of oil) so that tells me that oil was still getting pushed up into the boost pipes yes ??

Maybe the smoke was comming from the oil stuck in the intercooler? from a possibly faulty turbo or from excess blow by from the extra boost (18 psi) on old engine? because we did rebuild the turbo maybe the oil was just stuck in there from when the turbo was stuffed?

oh also we took the oil cap off when engine was running and gave it a rev and there was not any pressure in the crank case, just your normal oil spitting

You need a leak-down kit, most major mechanics will have one, it pressurises the cylinder and looks at how much air flows past the piston, provides a much better indication of ring-land/piston damage. Should be about $50-70.

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