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Discussion Starter #1
Evening all ,

I followed my GT 1.9 for the first time a few days ago - and I noticed that when driven hard there is a noticable swirl of black fuel smoke from the exhaust , is this normal ?

the car has been remapped - it does go well but I had not noticed this emission before .

all comments greatly apprecaited - good or bad !
 

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It seems to me that just about all turbo diesels smoke a bit when they are booted . I am no engineer but i think that there is a bit too much fuel going in untill the turbo is spinning up to speed . and therfore a bit of unburnt fuel goes out the pipe when you boot it

stands back and waits to be shot down in flames:)
 

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who did the remap?

a chuff of smoke whilst the turbo spools up is normal.

when its on boost, certainly from 2k up it should be really clean as long as its not overfuelling in the remap.

At high revs the turbo can't sustain the boost needed (the boost levels drop) so a bit of smoke at 4k upwards could be seen.

I think diesels run 20:1 air to fuel typically (maybe someone can confirm?) It is not good to have excess smoke, esp between 2k to 3k where it should be really clean.
If its smoking a bit throughout the rev band, then it may be worth getting the fuel map knocked down a little, it probably wouldn't make any odds to performance either.

That said, your egr could be sticking a little causing a similar effect?
 

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It seems to me that just about all turbo diesels smoke a bit when they are booted . I am no engineer but i think that there is a bit too much fuel going in untill the turbo is spinning up to speed . and therfore a bit of unburnt fuel goes out the pipe when you boot it

stands back and waits to be shot down in flames:)
Keep standing there, your spot on with your theory, but also it's oil that seeps through the turbo bearing being burnt,
 

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Discussion Starter #7
Keep standing there, your spot on with your theory, but also it's oil that seeps through the turbo bearing being burnt,
I thought unburnt diesel gave black smoke and engine oil gave bluish white smoke ? at least I'm hoping !
 

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I thought unburnt diesel gave black smoke and engine oil gave bluish white smoke ? at least I'm hoping !
That's how I understand it too (not that that means much ;)) ... if you improve the air flow (by fitting a high flow filter etc), then this can improve it ... although I've taken notice of other diesels since my remap and they all seem to smoke (even BMW's and Mercs ...)
 
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