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I just noticed the other day when I dropped from 5th to 3rd and accellerated hard I had some smoke coming out the exhaust. It was after 4000/4500 rpm with the turbo in full boost. Now if accelerated into those same rpms slowly without engaging the turbo, no smoke. Is this anything I should be concerned about? Is this what a "catch can" prevents? Thanks for any advise.
 

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Smoke out of these cars is never a good thing. Have you made any alterations to your tune recently? Check your air/fuel ratio, possibly running too rich or not burning off all the fuel for some reason.
 

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Smoke out of these cars is never a good thing. Have you made any alterations to your tune recently? Check your air/fuel ratio, possibly running too rich or not burning off all the fuel for some reason.
:whs:

That is, if you have a tune. If you don't then regardless it's an issue you should NOT have.
 

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Been driving manual my whole life. Don't rev match, I don't drive hard enough to worry about it.
I understand that you might have driven your whole life with a manual, but if I'm going from 5-3 under hard accelerating I'm going to rev match...

Edit: This shouldn't have to do with your issue, just my .02

Not trying to flame you. Just trying to give a nice tip and want to help get your issue solved.
 

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Probably just some carbon being blown out during your Italian Tuneup. Cars that are driven gently (ie normal driving) will put out some grey smoke during the occasional full throttle high RPM run. If you don't have any other symptoms and are not using any oil, I wouldn't worry about it.
 

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Probably just some carbon being blown out during your Italian Tuneup. Cars that are driven gently (ie normal driving) will put out some grey smoke during the occasional full throttle high RPM run. If you don't have any other symptoms and are not using any oil, I wouldn't worry about it.
Probably this. If you drive a lot in city or low rpm most of the time then romp on it occasionally, you probably broke off some carbon deposits or gunk building up on your intake valves. Wot or run some higher rpms now and then to get the valves hot. You may find the white to grey exhaust smoke that occurs on strong throttle/boost goes away for good.

Low rpm, lugging, short distance driving where the engine does not get up to full operational temperature are brutal overtime causing valve gunk, larger carbon deposits, rough on oil life, etc.
 

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OP if it makes you feel any better mine does this too. I don't usually look for it but i noticed it the other day i had a car with their headlights on behind me and when i got on it there was a little bit of smoke. I have a 2016 stock 6k mile ST. I think its probably normal for this car, i mean look how dirty our exhaust gets. Mine is driven about 95% city so i assume its just some carbon build up blowing out.
 

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Willing to bet it's a momentary rich condition due to it's dumping fuel to meet the demand(your foot to the floor). As long as it's not white or blue smoke you should be fine. Rather it run a tad rich than lean.
 

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Probably carbon build up getting burned off. Occasional WOT pulls are good for direct injection cars to clean off the intake valves. Also, it's just a characteristic of a DI motor. They produce more particulates in the emissions, which is why our exhaust tips turn black. Sounds normal unless it's excessive smoke, losing oil, losing coolant, etc


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Pretty sure its just carbon build up on the valves. Mine does that too occasionally, like a grayish whitish smoke comes out sometimes.
over time, the carbon build up can be a problem. VW makes a heavy duty fuel additive to help counter this, not sure if Ford does the same or not though.
 

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stock, most cars run rich. So if you are stock, seeing smoke is normal. When i do my datalogs in 4th, a crap load of black smoke comes out when I first get on it. I actually thought I would have a lot more now being cat less, but i have other issues that are probably causing it....
 
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