"black stuff" from the right 2 exhaust pipes

ThatBlueM2 · 04-28-2021, 02:42 PM

Hi everyone,

new here. Recently purchased a 2018 M2 with 26kkm on it. I'm not too savvy when it comes to cars, so bear with me please. Today I've noticed this:

As you can see, that black stuff, whatever it is, is only coming out of the right two pipes. Is this normal / what is it?

Thanks

CTSean · 04-28-2021, 02:54 PM

Carbon deposits from running while everything is cold. The exhaust valve closes off the left side so you only get the buildup on the right. Completely normal. If it's really stuck you might need a metal polish to remove it.

ThatBlueM2 · 04-28-2021, 02:59 PM

Thanks a lot for the explanation!

CalAcacian · 04-30-2021, 12:30 PM

Totally normal. If you want to get rid of it I suggest a device like the Mother's powercone on a drill with a polishing compound. But it will only ever be a temporary fix.

M Fifty · 04-30-2021, 04:26 PM

If you see some stainless steel tips you like the look of, fit them instead. They will clean up better.

04-28-2021, 02:42 PM	#1
ThatBlueM2 Enlisted Member 5 Rep 33 Posts Drives: BMW F87 M2 DCT Join Date: Apr 2021 Location: EU iTrader: (0)	"black stuff" from the right 2 exhaust pipes Hi everyone, new here. Recently purchased a 2018 M2 with 26kkm on it. I'm not too savvy when it comes to cars, so bear with me please. Today I've noticed this: As you can see, that black stuff, whatever it is, is only coming out of the right two pipes. Is this normal / what is it? Thanks
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04-28-2021, 02:54 PM	#2
CTSean First Lieutenant 323 Rep 392 Posts Drives: LCI BSM MT M2 Join Date: Dec 2018 Location: CT iTrader: (1)	Carbon deposits from running while everything is cold. The exhaust valve closes off the left side so you only get the buildup on the right. Completely normal. If it's really stuck you might need a metal polish to remove it.
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04-28-2021, 02:59 PM	#3
ThatBlueM2 Enlisted Member 5 Rep 33 Posts Drives: BMW F87 M2 DCT Join Date: Apr 2021 Location: EU iTrader: (0)	Thanks a lot for the explanation!
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04-30-2021, 12:30 PM	#4
CalAcacian Lieutenant 550 Rep 570 Posts Drives: 2018 M2 Join Date: Sep 2020 Location: Orange County, California iTrader: (0)	Totally normal. If you want to get rid of it I suggest a device like the Mother's powercone on a drill with a polishing compound. But it will only ever be a temporary fix.
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04-30-2021, 04:26 PM	#5
M Fifty Banned 844 Rep 1,962 Posts Drives: M2 & 330CI Join Date: May 2018 Location: The Interweb iTrader: (0)	If you see some stainless steel tips you like the look of, fit them instead. They will clean up better.
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