Fixed: Strong burnt oil smell from exhaust but no smoke

[X5only]

My X5 emits a strong burnt oil smell from exhaust but no smoke from the exhaust. I replaced the valve stem seals awhile ago (N62 engine) and the vehicle stopped smoking, but the burnt oil smell from exhaust persists. The exhaust tips always look clean, nonetheless. It's not sulphur or gas stink, just burnt oil smell. I thought the stink would go away after some time upon replacing the seals but nada after more than a year. I miss the days my X5 exhaust smell was all clean. I've transitioned from the smoke of shame to the stink of shame .

Any ideas and pointers? I'm an avid DIY'er. I have the following parts ready to be installed - fuel filter, spark plugs and oxygen sensors. A few days ago I did an oil change and replaced the leaking oil pressure sensor. Please, don't tell me it's now the cats ...

FIXED:

I had to install used and cleaned up front exhaust including the cats (the original cats were stolen), and also installed all new OS sensors. The stink is now all gone.