328i exhaust tail pipe

[TheTinkerer]

Hi guys, after sometime using my F30 I noticed there is difference in the twin exhaust tail pipe. One is clearly black while the other looks barely used. My of the time I drive in Comfort mode and rarely switched to Sport mode. Is it designed to shut off one pipe under normal driving condition (comfort mode)? Mind sharing your findings? It's good to know knowledge.Picture as below.View attachment 28051

 

[jason]

I have the Sports tips, but can clearly see the carbon deposits almost equally deposited on both tips. What's worrying are the white deposits, I am puzzled. Been reading that it could be due to the engine running lean or due to additives in our fuel. I use shell97 exclusively. Any ideas? I'll check with the SA tomorrow.

Jason
View attachment 28054

 

[Devillian]

Heyz, that's normal. The exhaust are valved, which means more gases would be going out only one the tailpipes during normal driving.

EDIT: Normal for one tailpipe to be blacker than the other. Am not referring to the white deposits on jason's car.

 

[Bruce_Z]

Heyz, that's normal. The exhaust are valved, which means more gases would be going out only one the tailpipes during normal driving.

EDIT: Normal for one tailpipe to be blacker than the other. Am not referring to the white deposits on jason's car.

Only the left one is "flapped" via an actuator, to improve low RPM performance. The flap opens at certain RPM...so a clean left nozzle may signify that the driver is very kind and gentle (throttle wise) ...

 

[splee]

Bro, you too sayang your car... That's why no carbon on one tip. Press harder and let the carbon out...

 

[Nightswan]

Join us in short drives and you will see both black! :burnout:

 

[splee]

I have the Sports tips, but can clearly see the carbon deposits almost equally deposited on both tips. What's worrying are the white deposits, I am puzzled. Been reading that it could be due to the engine running lean or due to additives in our fuel. I use shell97 exclusively. Any ideas? I'll check with the SA tomorrow.

Jason
View attachment 28054

Bro, this could be residue from car wash.....or other contamination from the environment and not from the engine. Why don't you clean it thoroughly and then check again to see if the same white stain comes back.

 

[TheTinkerer]

I have the Sports tips, but can clearly see the carbon deposits almost equally deposited on both tips. What's worrying are the white deposits, I am puzzled. Been reading that it could be due to the engine running lean or due to additives in our fuel. I use shell97 exclusively. Any ideas? I'll check with the SA tomorrow.

Jason
View attachment 28054

I've been using Shell 97 exclusively for the first few months and do not spot any white deposits as shown in your image. So, may not be the fuel additives.

 

[mizhan]

This exhaust flap system has been a feature in the 3 series since the E36 to improve low rpm response as mentioned by Bruce. My 328i had it.

 

[achtung]

The flap is more for sound suppression at low RPM contrary to popular belief !!!
The flap gives you a bit more back pressure and reduces the volume of the exhaust note.

And ur car won't be any faster or slower without that flap.

 

[TheTinkerer]

Join us in short drives and you will see both black! :burnout:

That souns like a good idea. But i don't have the skills to drive fast...