BMW E90 323i smoke after decat exhaust

[ReddyBMW]

Good evening gents

I have done a decat and free flow exhaust system on my 2012 bmw e90 323i. When I reach a complete dead stop, white smoke comes out of the tailpipes. The car doesn't have any cat foolers on it, no error codes are showing on dash. The car does seem to be burning rich, can smell fuel when its idling. How do I get rid of the smoke, will fitting cat foolers solve the problem? I don't want to put the cats back, the car sounds wild without it!
Also is it common for valve stem seals to be done on the N52? Car is currently on just under 208 000kms.
Appreciate the advice to follow.
Regards
Previn

 

[freakoid9000]

Check that your pcv system is working properly. Cats can mask the smoke - so once you remove them... smoke! Cars that have been decatted also tend to be smellier, so that might explain the smell you are getting at idle.

 

[Gordvisr]

Hallo, valve stem seal are not a common problem on the N52 range, depending on the oil service. I owned one, sold a 220 K, currently on 245 K never opened. Then another N52 which i still own, on 225K currently, and also engine was never opened. Both decated never had a smoke problem, as previously mentioned, your PCV system might be faulty. hope you get sorted soon.

 

[ReddyBMW]

Thanks for the advice guys, really appreciate it.
Just one question, to replace the pcv, do I need to buy a new valve cover or can i purchase the pcv as a separate item from a spare shop?

 

[Gordvisr]

Before buying anything, get your car properly diagnosed before spending money. With PCV system there should be an oil smell too, of which you were not mentioning in your first post. If the car is cold, on idle have some white smoke, this is normal ( water vapour ) after a run and engine on temp smoke should be gone ? Then maybe just a slight tune. all four BMW's i have owned, decated had the same symptoms, smelled rich.