I figured I should mention this here.
After getting the EGR cooler recall done at my dealership in the summer of 2020 (at least the 2020 X3 M40i loaner was nice!), I noticed that I would get raw diesel exhaust smells in the cabin through the vents on cold starts.
I first thought it was the seal for the turbo VNT actuator, but after putting my hands around there, I found the problem:
After valve cover gasket and Simple Green:
The gasket between the EGR cooler and the exhaust manifold is completely missing.
Here is what it looks like normally:
That area lets out plenty of exhaust gas, and you can see evidence of it from the soot marks on the head and turbo actuator housing.
My problems were that I'd get a lot of exhaust fumes in the cabin, especially on startups.
I fixed it myself; I won't let my dealer touch the car anymore.
BMW Part number 11628576287 (~$8)
Bonus Round!
1. My dad's X3 28d came from the dealer 2 weeks ago, EGR cooler recall completed by the same dealer:
2. My local friend's 328d sedan had the EGR cooler recall done at the same dealer:
3. A friend in Europe showed me a picture of his X3 18d sDrive (with the N47), and it too was the same:
It looks like there are "forgetful" techs everywhere. Check your car. I'm curious how many other missing gaskets there are around. Make your dealer fix it.
My dealer's service manager
tried to convince me that the gasket is not visible when it's installed.
I'd be willing to claim that it's invisible when it's not installed!
What's funny is that it comes in the BMW EGR cooler recall parts kit from BMW:
(at my BMW dealership, I went into the shop to see my car while it was in progress).
tl;dr check your EGR cooler to exhaust manifold gasket. Dealer techs don't always install them. This is 4 examples I know of.