[weiyu435i]

I've recently noticed a faint white smoke and burning smell coming from the passenger side engine bay of my 435i after driving anything more than a couple miles.

It looks like it's coming from the o2 sensor (could be wrong) but I can't tell if that's the actual problem or just a symptom of a bigger issue (leak somewhere?). There's no engine light and oil levels look fine.

I have CPO warranty for one more week so I'm planning to take it in and get it checked, hopefully covered. But before I do, anything I should check beforehand that i'm missing? Also, why would the sensor corrode like that? Thanks.

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[celsdogg]

I didn't look at the video but my guess would be a leaking valve cover gasket. oil leaking down and burning on the exhaust. dealer will replace it if necessary.

[Tommy-G]

I just dealt with this on my E93 335. Mine was a leaking rear main seal about 140k miles on her. Drips down on the catalytic converter. Repair was expensive and my guys in my bodyshop werent comfortable doing it. We took an old heat shield from a wreck and diverted the oil away from the cat.

Take it to the dealer and they will tell you the car is going to start on fire etc etc. Sucks but seems to be pretty common (and embarassing when stopped at a light)

[pjekoo]

Hello Tommy, you mentioned using old heat shield to diverte the oil drip away from the cat, did that actually work? I'm having a slow leak but if this trick will work, I'll try it.

Paul

[thejeremyman9]

Originally Posted by pjekoo

Hello Tommy, you mentioned using old heat shield to diverte the oil drip away from the cat, did that actually work? I'm having a slow leak but if this trick will work, I'll try it.

Paul

Just fix the VCG leak before it becomes a hazard or more serious problem