Some of you may remember the thread I posted a couple weeks ago:

https://my350z.com/forum/forced-induction/235502-black-smoke-from-ttz.html

There has been a development:

Since the turbos went on (about a year ago), the car has always run VERY clean. In fact, there was less soot on my tail pipes than when I was stock. Now that winter is here, I don't drive the car as much (two times in the last week). In the last two times I drove the car, my tail pipes went from spotless to COVERED in black soot. I drove the car to work today and parked the car in a poorly vented underground garage. When I got out of the car, I noticed the faint (but distinct) smell of burning oil.

I am guessing this problem is one out of a couple things:

1) I am blowing oil through the turbo seals
2) I blew out one or both cats, and I am now notcing the mess that the cats used to burn off (though I would have assumed that the car would be noticably noisier if that was the case, which it is not)
3) I have some "minor" engine problem like a cracked ring, ring-land, etc...

Thoughts?

 

do a compression check

 

does the general sound of your motor sound the same? does it idle different?

 

It sounds the same... still idles nice and smooth, no strange noises under load.

 

In my extremely uneducated opinion I am sure you are just fine. However I still think you should build your motor.

 

I've blown/damaged a few motors in my life time and you ALWAYS hear something that isn't normal. You can get heat damage, before blowing the engine and you'll hear a knocking sound from a bent rod.

 

If you're running cats on your setup you could have fouled out the cats since it's running so rich. That could might explain some of the soot. I've always gotten lots of soot especially when I am full throttle a lot. It's just unburnt fuel from the very rich combustion. I don't have cats though. My car smells slightly of oil which I can attribute to my PCV system (not having a catch can). I just pulled my motor last week since I'm doing a build and when I took off the upper plenum there was A LOT of oil in the plenum. We're talking little pools. That oil builds up and more and more of it is burned during normal combustion. Just a fact of life of having a boosted car without a catch can.

If your car drives/sounds fine and isn't leaking anything, I wouldn't be worried at all. Try an oil catch can too...

 

i heard that sound first hand. it was terible. i wake up at night screaming sometimes because of that sound.

 

My bumper is always covered in soot after long periods of driving (especially after highway trips). I'm pretty sure my motor is still running just fine, just a little on the rich side (hasn't done a compression test).

 

Blown motors have holes in the bottom. There is generally pieces from inside the motor on the highway, and oil splashed everywhere.

 

I agree, if it sounds ok that should rule out rods or bearings, the cats are a good place to start than do the compression test.

Don't worry though this does not sound serious.

 

Not always, or even usually. Yes there have been some crazy blown motors around here, and yes, the VQ seems to sprout holes more often than many other platforms, but not all blown motors are catastrophic failures.

Motors can still run with blown gaskets, cracked rings, ringlands, bent rods, bent valves, etc.

 

I hope it is the cats, but I will find out soon enough. The smell of burning oil is what really concerns me, but it sounds like I am not the only one with that issue... especially considering that I am not running a catch can. I guess it may be time for one.

 

I literally had oil pooled up in my lower plenum after 15K boosted miles without a catch can, and that was definitely where my oil was going and the produced the nice smell at idle. I will be adding a catch can with my new setup.

 

does a oil catch can help that much?where can i pick one up?

 

Forged Performance carries a Greddy one for about $100. You call you might get it for a little less. I think the Greddy is the better looking ones of them all. I have seen them for $80 though. Just look around.

 

yea i found one at Vividracing for $90

 

That is not always the case...been there done that.