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Discussion Starter · #1 ·
Hey guys i have a question for you all and im hoping you can give me some ideas on how to deal with the issue. The problem i have found is that when i boost i blow grey/black smoke (well im assuming its grey/black because i cant see it unless its at night and theres a car driving behind me so i can see it in their head lights.

The head has been replaced about 40,000ks ago and car still runs fine, like there is no signs to me that anything is wrong other then the smoke? It still boosts like it used to however iv been trying to avoid boosting because i dont want to cause anymore damage to whatever it is that could be causing it.

I have a feeling its going to be something to do with my turbo which scares me a little because thats one area that i am very bad in and dont really have mates here in brisbane who could help me out like i do back home and so id have to wait for them to come visit. Any help or possible solutions to my problem is greatly apreciated as i would like to keep this car on the road for as long as possible.

Thanks everyone and have a great night.
 

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Hmmm.. sounds like your turbo is going :(
Not 100% sure, because ive never had a turbo'd car, but similar thing happened to my friends car, few days down the track.. bye bye to the turbo :(
Does it make a strange noise? Like whooping/scrapping noise?
 

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Discussion Starter · #3 ·
no it doesnt it just drives like it always has as far as i can remember. Its still smooth to drive and its not jerky and it still does 9lb of boost. My other question is if i get another mx6 turbo will i be able to bolt off my old one and rebolt the new one? With the correct bits and pieces?
 

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so your only getting smoke while boosting?

blue smoke = turbo seals
white smoke/sweet smell = coolant
Running rich causes black smoke/dark grey in most cases.

Have you done a boost leak test?

Check your turbo for shaft play?
 

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I've always been told it's normal for blackish/grey smoke to come out under boost. I mean, the car is dumping in a whole lot of fuel to compensate for the boost levels, and the air that's coming in. So you're naturally going to get a whole lot of smoke coming out under boost. Unless you're blowing extreme amounts, I personally wouldn't worry too much about it.
 

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Discussion Starter · #6 ·
how do i check for shaft play? I havnt changed my coolant for a while i think ill do that when i get home iv been meaning to do it. How do i do a boost leak test? Oh and thanks everyone for the help as you can understand im quite concerned about the old girl.
 

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dont turbo cars get blow by anyways if its blue?

if you see some skylines from behidn they blow graysmoke but most are far from stock. mild mods, bigger injectors and fuel pumps will do i would say.

hows your fuel eco?
 

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Discussion Starter · #8 ·
i actually get quite bad fuel economy. Well i think it is, i fill up with a full tank of bp ultimate and only get 320ks from the tank and thats me driving like a granny, if i do anyhting but that i get like 280ks i think.
 

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A stock ECU'd Mx-6 will do the following

apon load it will open up the injectors before it increases the timming.

Auto's are worse and you will see a normal over enrichment of black.gray unburnt fuel out the rear.

in msot cases due to you changing down and flattening it.

you will also get this when you go to WOT. it maybe a little more consistant and you should get a tail of exhuast smoke.
How dark and dense it is depends on your exhaust - spark - timming and overall condition of car - More boost will make it worse.

to remove - add Woo - chip ECU interceptor aka unichip etc.

Or aftermarket ECU.

Yes all turbo cars will go from nice clean clear exhaust to slighlty richer smell but should never turn out black in cloud. It might be more noticable exhaust but it should only be a shade darker then a N/A engine.

I use to have old video where one could see a clean burn. A good tune won't cloud up.
 

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sounds like extra fuelling. Do what rod said

Any white smoke at idle would indicate bad oil seals in turbo.
 

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Discussion Starter · #11 ·
awsome thank you so much for all of the help guys iv been considering getting a woo-chip and now i have every reason to. Just have to keep saving. Have a good night everyone
 

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yeah you would definately know if your turbo seal was going bad. the smell of oil burning out your exhaust is the most annoying thing. id say its dumping fuel.
 

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Unburnt fuel is black/grey smoke.
Turbo seals is white smoke.
Worn piston rings is Blue coloured.
 

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Discussion Starter · #14 ·
its definatly a blacky grey colour
 

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True, I am pretty sure when I booted it the other day was getting white smoke from my 626 turbo. Anyone know of a good place to get turbos rebuilt or am i better off to upgrade/get a second hand turbo?

What turbos fit straight on/bolt on for the standard manifold?
 

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I have noticed a lot of turbo cars produce slightly darker exhaust gas when in WOT as Rod was saying.

The other day I was behind a Porsche Cayenne turbo. Driver was driving like a crazy person. WOT at the lights and a cloud of black smoke resulted (it also went very fast). I have also been behind Odin's Skyline at WOT and it blew a little darker exhaust. The Cosmo has slightly darker exhaust too at WOT (but its a rotary so...).
 

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GCG in sydney are meant to be very good.
I decided that as my engine was being done I'll reco the turbo, they charge $675 for rebuild with hone etc, if you need new turbnine/impeller etc it gets expensive.

go to GCG Ltd
 

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nothing that i know of will bolt straight on....its a personal choice really, either pay to reco the little snail or upgrade to something that wont run out of puff before 6000rpm....for a couple hundred extra ontop of the standard reco price (depending on what turbo you go for) you can have a decent turbo. which is gonna be more expensive of course. im glad i did though...
 
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