1MeanTA

Ok guys, Ive used the search tool and havent run across a thread that described my exact issue (and most of them that were close were OLD/or the original poster never posted a fix) so I went ahead and made one of my own.

Two nights ago I finished installing longtubes/ORY, deleted my EGR, and put plugs and wires in my 99 WS6..(94k miles) and I am noticing some major smoke from the exhaust (NOT THE HEADERS THEMSELVES, NOT UNDER HOOD, BUT OUT THE BACK)

I do NOT currently have 02 sims in the rear as I was going to have them deleted by a buddy with LS1edit. The car has not used oil or smoked ever before...but I am getting a large amount of blueish/black smoke outta the exhaust, mainly under hard accel or on decel. I am aware the cars can have issues with valve guides and such, but I have a hard time believing that I would notice absolutely no smoke 3 days ago and now have a LARGE amount of smoke.

Can this be EGR related? Possibly related to having no rear 02's?

I went ahead and stuck a new (factory) pcv valve in it to see if by chance it made any difference and it didnt help. Any insight?

I would greatly appreciate ANY knowledge on this subject, as I am bummed out beyond belief. Thanks!

btw...the only mods to the car are the headers/ORY/SLP loudmouth, lid/smooth bellow, 150 shot nitrous plate kit.

runtwrestlin

iTrader: (3)

I know not having the rear O2s tuned out/off will cause you to trip a code, but I don't konw if that would cause your issue.
After you deleted your EGR did you retune the PCM? Also, are you using the same O2 sensors now that you used when you 1st put the headers on? I've heard that can ruin the O2 sensors.

I don't think any of those problems by itself would cause your issue, but perhaps all of them at once has?

ds98formula

iTrader: (3)

Rear O2s are not any part of the problem as the controll nothing. Did you delete the cats at the time of installing the headers? It is also not the egr all it did was take air and put it in the intake to reduce nox

Nissan LS240

iTrader: (1)

is it blue or black smoke? blue would indicate oil being burned and black would be you're running rich, when I deleted the cats off my car i noticed large amounts of blue smoke, replaced valve guide seals and it went away, is it worse when you crank it up first thing in the morning, if so it's probably your valve guide seals. if it doesn't do it in the morning and only under hard accel, might be a blow by issue, could be rings or pcv system sucking oil, don't see how long tubes would have affected anything except maybe its now allowing more exhaust to pass than before, egr isn't turned on, on hard accel or idle, only when cruising, and it only works when the engine is warm, don't think it would have caused your smoke issue.

1MeanTA

Im gonna say its MORE blue than black, i noticed VERY intermittently that the car would puff a small amount of blue smoke on initial startup (before the header install) which i figured to be valve guide seals... but this is on accel, and decel...and smoke is BILLOWING out..I just have a hard time believe it to be blow by when I NEVER noticed any smoke on hard accel or even when revving the car hard, and just by deleting the cats and adding headers as stated, now im a mobile misquito killer. ha.

Any other ideas?

LeanPocket

iTrader: (6)

sounds like ur burning oil, thats what the blue smoke typically is

1MeanTA

I appreciate the input, and yes, I know typically blue smoke would be oil...

The issue is figuring out why 3 days ago with no headers the car did not smoke whatsoever, and after installing headers i am literally leaving a cloud behind me on hard accel and between shifts.

Will post up after i pull the throttle off and check the intake.

Any more diagnosis ideas are appreciated.

ds98formula

iTrader: (3)

Take a vid if you can of the smoke pourin out. Could have snapped a ring....

Compression and leak down test will tell alot

TheSilverOne

iTrader: (22)

the 150 shot...were the necessary precautions taken for this?

1MeanTA

Yes, had an ls1 specific wet kit, and ACTUALLLY only sprayed 150 twice, sprayed 100 any other time, ran TR6 plugs on a digital window switch-sprayed from 3500-5500 rpm range...in most of what I read.. and had friends with the same setup, there wasnt much needed on that kit other than the plugs...sprayed on the dyno where fuel trims were in the norm.

I understand this couldve made a weak point...but if it has, I cant understand seeing no smoke out of the car at all, and only losing maybe .5 qts between oil changes...to doing a header install and having lots of smoke on accel and decel. never at idle or on startup

mikedamageinc

iTrader: (49)

What is your mileage? You should try a compression and leak down test.

Mine does the same-blue smoke above ~5K. I think it was more noticeable after full exhaust install. My compression is good, new valve seals so guides my be my issue. Just my thoughts.

1MeanTA

97k on the clock. Was not able to get parts on yesterday, hopefully gonna pull seven and eight and check plug condition, leakdown and compression test today to see where I stand.

ds98formula

iTrader: (3)

Let us know how those test pan out.