[FloridaMan_G82]

About six months ago i got my turbos replaced under warranty on my 2007 e92 335i at the dealer. about a month later i started smelling burning oil/plastic smell, since i had just done an oil change, i thought maybe some oil had spilled and was burning off. a few weeks later i still had the same smell, so i brought my car back to the dealer. they said it was the oil filter housing gasket and quoted me 800$ to fix it, so i ordered the 12$ part from ecs and did it myself. there is no leak now from the housing, yet i am still smelling the burning oil/plastic smell, i saw a small bit of smoke come from the top of the motor down on the turbo side, and it looks like the o2 sensor wires are touching some turbo piping, but they do not appear to be burnt. I believe I remember the service advisor at BMW saying that there is a 2 year warranty on any work they do so I am probably going to bring it back to them. As many other dealers, these people are assholes and im sure they will refuse to do any work for free. has anyone had this problem or have any information about it? there is no oil in the belly pan, never low on oil, even after 5000 miles. there must be a small amount leaking out by the turbo and immediately being burnt and smelling? im not sure! any input would be very helpful! thanks everyone!!

[FloridaMan_G82]

on a side note, when i was replacing the oil filter gasket, there was a bit of oil in my intake, and the valves had a lot of carbon buildup, but this cant contribute to the smell/smoke. the gasket needed to be replaced, but i just dont think it was the root cause of the smell.

[6BATMAN6]

I have this smell and the culprit was a cracked valve cover ..

[suprchrgd]

i have 80k on mine and my valve cover gasket was leaking and dripping down onto the mani's. BMW wanted $1100

bought the gasket for $37 from getbmwparts.com and 2 hrs of my time and problem solved

[atx335]

Took me a while to find the threads but FINALLY. I have been having this exact same problem for the last two months and I am ready to pull my hair out.

- Turbos were replaced 10k miles ago by BMW

- New injectors, VCG, RB pcv valve and new hose

- No loss of boost, smoke under boost, only at idle once it is warm

- The smell, of god the smell, so sick of the car wreaking of burnt oil

- No leaks that I can find aside from oil leaking from the rear turbo inlet

I had no problems, car was running good, just replaced injectors. I noticed a really tiny leak from my original VCG so I replaced it and cleaned the PCV system. Install the VC, button everything up and bam, here comes the smell, burning oil and confusion.

I was CONVINCED it was my vent hose, I cleaned out the PCV so it was nice and open. The oil was coming from the rear inlet so I just assumed something was failing in the vent hose and it was allowing the car to pull oil in.

Replaced the vent hose, no change. Ok WTF. Same symptoms, no answer. Still hit boost target, don't consistently see smoke but every damn time I stop or park the car it smells awful. Here is when it smokes, I should mention it seems to be totally sporadic, IE not always.

- Turning
- Stopping
- Stop and go traffic
- Idle

Now here is where is really gets weird. After a series of pulls a few weeks ago I come home, pull up to the front of the house and read the logs. I also rev a few times to check some wastegate settings. I pull away and see the smoke, turn around and there is a good cup of oil on the ground...

At this point I am assuming it is my turbo seals or my valve guides. I just can't understand why it is tied to the VCG?!?!?!

Since the turbos have low miles and I am not seeing a drop in boost I am hoping I can just rebuild them. Either way this is really annoying.

[JamesM3M5]

So if you see that much oil on the ground, where is it coming from?

You will need to recheck valve cover gasket installation, PCV valve, and intake pipes. There will always be some oil in the intake due to the PCV design, but excessive oil coming from the PCV and dumping into the rear turbo could mean a crankcase leak due to a folded or improperly installed VC gasket or something similar. Crankcase air leaks allow the intake to suck a whole lot more volume of air, and with it, oil vapor, into the intake.

When I did my VC gasket, I hosed the cover out with degreaser and a pressure washer. New gasket, Hylomar around the PCV ports, and Motul 5W40 Xcess. The oil drip from the rear turbo inlet disappeared and still hasn't come back after 3 years. Typically for customers I recommend a new valve cover complete, so there's no issue with degraded PCV valves, warped or brittle plastic, and reduced risk of a come-back for any oil/PCV issues.

What oil are you using?

[Scrippy]

Put her on ramps. Take off the belly pan. Inspect both turbo body's. There are coolant vent lines and oil lines going into the turbo body. If the dealer didn't change every O-ring on those hoses, they'd leak. You would clearly see burnt oil on the turbo body and hose mounting surfaces or on the bottom of center housing, as gravity will show ya.

[The Convert]

Most likely culprit is going to be a cracked valve cover on the injector side between cylinders 3 & 4. Take a peek and report back.

[Boosted_N54]

Stem valve leak

[FloridaMan_G82]

on my car it turned out to be the turbo oil feed seal. bmw f'ed it up when they replaced my turbos. they tried to tell me it was the oil filter housing gasket and wanted to charge 800, so i did it myself for 12$, and brought it back with the same issue. they agreed it was their fault and fixed it for free. all good now! sounds like the same issue to me!

Originally Posted by atx335

Took me a while to find the threads but FINALLY. I have been having this exact same problem for the last two months and I am ready to pull my hair out.

- Turbos were replaced 10k miles ago by BMW

- New injectors, VCG, RB pcv valve and new hose

- No loss of boost, smoke under boost, only at idle once it is warm

- The smell, of god the smell, so sick of the car wreaking of burnt oil

- No leaks that I can find aside from oil leaking from the rear turbo inlet

I had no problems, car was running good, just replaced injectors. I noticed a really tiny leak from my original VCG so I replaced it and cleaned the PCV system. Install the VC, button everything up and bam, here comes the smell, burning oil and confusion.

I was CONVINCED it was my vent hose, I cleaned out the PCV so it was nice and open. The oil was coming from the rear inlet so I just assumed something was failing in the vent hose and it was allowing the car to pull oil in.

Replaced the vent hose, no change. Ok WTF. Same symptoms, no answer. Still hit boost target, don't consistently see smoke but every damn time I stop or park the car it smells awful. Here is when it smokes, I should mention it seems to be totally sporadic, IE not always.

- Turning
- Stopping
- Stop and go traffic
- Idle

Now here is where is really gets weird. After a series of pulls a few weeks ago I come home, pull up to the front of the house and read the logs. I also rev a few times to check some wastegate settings. I pull away and see the smoke, turn around and there is a good cup of oil on the ground...

At this point I am assuming it is my turbo seals or my valve guides. I just can't understand why it is tied to the VCG?!?!?!

Since the turbos have low miles and I am not seeing a drop in boost I am hoping I can just rebuild them. Either way this is really annoying.

[J. Dub]

Same problem here. Glad to find the thread

[limitdown]

My burnt oil smell turned out to 2 leaky turbo oil pipes. One was a turbo oil intake pipe and the other was a turbo oil drain pipe. Being on the hot side, the temps are so high that some of the oil leaking there got burnt into the atmosphere.
The drain pipe is not too difficult to get to, but if I remember correctly, the oil intake pipes were much more difficult to reach for my Indy. I ended up replacing all of the pipes and gaskets down there. 2 oil intake pipes, 2 oil drain pipes, 4 turbo water pipes. IIRC, the labor was quite high compared to the price of the parts, so I just replaced all of the pipes as a preventative measure.
The turbo water pipes have rubber sections that are prone to problems with age.
My car is also older (a 2007), so many of the potentially weak spots are starting to break.