[KillaF30]

Okay so, slightly vague post as i havent gotten around to taking the car in for a diagnostic yet, just wanted to see if anyone has had a similar issue:

Car is a 2015 335i xDrive:
68k miles
Upgraded charge pipe
Catless downpipe
K&N drop in filter
Bootmod3 stage 1
Airlift 3p
Res delete

After installing the downpipe i notice smoke didnt think much of it got tuned around march, now when the car sits and idles when i drive off its a cloud of smoke till the exhaust clears out, as if oil is pooling and burning somewhere, i removed the exhaust looked in the downpipe it was clean as a whistle. I have a picture of what it looks like when i pull off.

Any ideas or things to check before i bring it in would be nice, thanks

[jh_f30]

https://www.google.com/amp/s/blog.fi...or-telling-me/

[obeeone]

I haven't had an issue on mine like this, but past experience points me to a couple of possibilities. On a non turbo car I would first think valve seals or PCV system issue, but on a turbo the first place would be the hot side turbo seals. Being that you checked the DP and said it was clean as a whistle I wouldn't think that's your issue, but it could be just small enough to not leave residue yet.
I have not heard of valve seal issues on the N55 so I would likely rule that out and checking the pcv system isn't that hard.

There is some information about pulling the oil fill cap while the car is running and checking to see if there is a large amount of vacuum when trying to remove the cap. As well it will cause your engine to stumble and run rough a little when pulling the cap as well.

See video (F10, but same system)

[KillaF30]

Originally Posted by obeeone

I haven't had an issue on mine like this, but past experience points me to a couple of possibilities. On a non turbo car I would first think valve seals or PCV system issue, but on a turbo the first place would be the hot side turbo seals. Being that you checked the DP and said it was clean as a whistle I wouldn't think that's your issue, but it could be just small enough to not leave residue yet.
I have not heard of valve seal issues on the N55 so I would likely rule that out and checking the pcv system isn't that hard.

There is some information about pulling the oil fill cap while the car is running and checking to see if there is a large amount of vacuum when trying to remove the cap. As well it will cause your engine to stumble and run rough a little when pulling the cap as well.

See video (F10, but same system)

Appreciate you bro, gonna go deeper into the pcv system