Alright, so as of late I've experienced considerable oil consumption, without any idea where it's going. From the cabin, I was not able to see or smell oil burning, nor are there leaks. Going through about 1 quart every 750 - 1000 miles.

Car was detonating for awhile. Installed the Aquamist system, run 80/20 methanol/water - detonation reduced to rare occasions.

Installed catch can and PCV last week. Running 15w50 as per APS' instructions.

I beat the hell out of the car - 31,000 boosted mi. with the way I drive it's bound to happen. But not quite sure WHY the car is smoking...?

GF followed me tonight: said at idle and cruise there is no smoke visible. Under WOT there is an incredible amount of whitish-grey smoke that comes out, disappears when I shift, comes back under intense load. I can't see it from the cabin. No smoke when I decellerate, no smoke after I come to speed and cruise.

Oil appears fine, not milky. Radiator fluid levels and temp are OK. I've comfortably r/o a head-gasket issue. I have not performed a compression test yet (might do tomorrow).

I did pull my intake tube: bone dry. No oil residue, so I don't THINK the turbo (at least on the compression side) is passing oil. So, leaves me with 3 options:

a) turbo oil leak on exhaust side (throwback from when I screwed up the pump install)?
b) worn/damaged rings passing oil (from detonation and wear)?
c) smoke is from water/alcohol injection (hence the white-ness of the smoke)?

I checked the catch can, not enough oil in there (yet) to see it in the sight, but the sight has oily spots in the tube, so there's oily vapor in there. t's only eben about 300 mi. thus far...

I pulled plugs from Cyl 1 and 2, they both look exactly the same (pic below).

Anyone with any thoughtful input would be greatly appreciated - TIA!

 

oil RARELY reaches the throttle body pipe, even when my IC had a pool of oil in the bottom. you need to undo the bottom silicone coupler on the ic and look inside it. thats the best way to rule out oil from the turbo.

 

Gotcha - though it should be noted that when I miswired the scav pump, I had oil EVERYWHERE in my intake, coming out the BOV, coating the MAF sensor, etc. No such problems anymore.

It seems that consuming one quart every 1,000 mi. is not necessarily ABNORMAL according to Nissan, and some kids over at NASIOC and SRT forums have similar consumption issues. So, MAYBE, just MAYBE the oil comsumption issue isn't much of an issue? The tailpipe has charcoal-like residue on it, not oily or grimey as you would expect from passing oil.

The plugs appear to be relatively normal *sigh*

The more thought I put into this, the more I think the oil and smoke issues are not inter-related, and that it's a result of my W/M injection?

 

sorry to hear it's smoking. The engine seems to keep on going though with as much hell as you've put it through and for how long you've been doing it


does the smoke go away if you switch to 50/50 methanol/water? I might be wrong but I think I may have heard using mostly methanol can cause some sorta issue - forgot what though

 

Dunno - tomorrow I'll pull the fuse and run it w/o the injection to see if I can emulate the smoking. I watched the gf run the car up and down the street - to me, the smoking wasn't obnoxious by any means (looked like it was running rich) but it's difficult to make that assessment by streetlight.

The plugs would indicate that I'm not burning oil (in those 2 cylinders, anyways), so tomorrow afternoon I'll screw with it a little more.

 

For what it's worth... http://images.google.com/imgres?imgu...006-16,GGLG:en

 

I have suffered turbo seal destruction twice!!! and both times, there was oil in the intsake tube, all the way to the throttle body

It sounds like the rings may be wearing, you obviously have a good idea about the symptoms and diagnosis...have you performed a leakdown? this will tell you a ton of info as far as comparative data between each cylinder, if this reveals a lacking cylinder you will be able to pinpoint your problem..

a bad turbo will smoke during decel...and/or at idle (cartridge is not pressurized and oil seeps through)

bad valve stem seals will smoke at start up and at low idle, usually not under full throttle

bad rings will usually smoke under load

headgasket/headlift can allow coolant into the combustion chamber and cause a whitish/clear water vapor/smoke under idle/throttle/decel...

good luck...

-TODD

 

A little bit of whitish/grey smoke under heavy throttle isnt anything unusual. As we all know, its very hard to determine the exact color of the smoke, when observing the car from behind. Grey color to some people, could be blackish to others.

Your plug looks like your engine is running a tad lean. The white porceline, in conjucntion with the salt and pepper apperance is indicative of lean detonation. You mentioned you had some det issues earlier that were resolved, so this might be the left over.

After 30K miles, I tend to agree with Todd. I think this motor is just a little bit tired, resulting in the high oil consumption. I dont think you have a leaky turbo, IMHO. Do a compression and leakdown test to comfirm the health of the engine.

What are your AF ratios at WOT?

 

yeah i agree, oil can fill the intake charge pipe. my point was that, just because there isnt any there doesnt mean it isnt happening, he should check the IC. he and i have the same kit, and have had the same problem, my intake pipe was clean and the IC had half an inch of standing oil. if i had just gone by the charge pipe, i would have been wrong.

you have also been running built motors with twins running much higher boost than we run, so you have a stronger intake charge.

 

I drive the hell out of my car as well (30k of boosted miles on a stock motor) and it runs way strong still. But when I realy get on it at WOT i get a mist out of my exhaust as well, I always thought that was just fuel from running so rich.

 

I'll post vids a little later this evening - nice day out, day off, time to kill...

In response to Sharif's question: AFR at WOT is about 11.4 - 11.8 nearing redline

 

good point

 

Well - no luck in re-creating the smoking, unless Toyos count:

https://my350z.com/forum/showthread....83#post2436283

 

Just curious Joe.. What boost level are you running right now? What's your peak boost and the boost level around 6000rpm? For what it's worth, my sister with Audi TT roadster quattro carries around oil and fills up once or twice a month... Even stock turbo cars consume oil.. Just curious, do you have a turbo timer? Do you let it cool off before turning off the car?