[M_Dennis87]

I figured I'd also post this here, as it wasn't getting much action in the NA Engine section...

So I've been chasing some smells when the heat is on and leaks lately with my car. It's a 2012 E91 with about 55k on the clock. I recently replaced a leaking oil filter housing gasket and cleaned everything up in the engine bay, but I'm still smelling a slight burning smell on startup. Doesn't quite smell like burning oil either, though there is still some oil residue under the intake manifold that I think is from the OFHG leak. There is no oil in the spark plug wells.

So I still have the burning smell when the heat is on which is particularly bad at startup, but does eventually go away after the engine is warmed up. Another symptom I've noticed is sometimes on startup, the rpms fluctuate. This usually goes away after 10-20 seconds. Also, lately I have noticed a consistent white smoke from the exhaust. I know it's winter, so I'm not sure this is a symptom of anything but driving in the winter, but I figure it may be worth mentioning.

So my thoughts are it could be relating to pcv breather valve. I've seen a couple recalls that could be related (NHTSA 17V676 Blower Motor Wiring may Overheat, 17V683 PCV Heater may Short Circuit), though MY model year isn't listed on the recall. Not sure if it's because it's a 2012 and all N52 3-series cars ended production in 2011 except for the wagon. Either way, any help or info would be greatly appreciated.

[jsunma]

Any codes? I'd definitely say you should read out the codes (if any) as a starting point.

Beyond that (and really, I'd let the codes lead this investigation vs just guessing), the "fluctuating rpm" is a good sign of a valve cover gasket leak. If you've already had and fixed the OFG leak, the VCG leak is quite possibly present.

Also, your "burning smell" really could be oil from a VCG leak. The fact that you smell it when the heat is on could be (it is on my car) because the ventilation system is pulling in "fresh" air from under the hood...but it's NOT fresh because it contains burning oil smell from where your VCG is leaking a tiny bit of oil down on to the cats..which sit directly in line to catch an oil leak from the VCG. Turn the vent to recirculate and see if the smell goes away (when you're in the car). If you have your climate control set to Auto, then it's working harder at start up and possibly pulling more air, and hence more smell.

White smoke? Hummmmm. Are you losing coolant? Have you checked the level there? My guess (and that's all any of this is) is that you're probably fine so far as cooling leaks and you'r'e not actually blowing an unusual amount of steam from the exhaust.

And to your original point/post title, I don't think that this has anything to do with the PVC heater recall. That's an electrical issue. When they do that recall (I've had it done), they just replace the heater circuit. These cars don't have separate PVC valves...the PVC is integral to the valve cover. They're not replacing peoples' valve covers (for free) under this recall.

Good luck! And report back on what you find.

[lowrydr310]

Is your oil pan gasket leaking?

I fixed all of my oil leaks except the oil pan gasket. It's a minor leak, no drips on the ground or anything, but apparently it's enough to still give off a faint oil burning smell when the engine is hot.