[dieselgg]

Hi, on my 2009 335i, I have noticed high oil consumption. In the past few weeks I have to added about a 0.5 quarts of oil after 1300km (800 miles). This morning it was at full, but then driving home it is now at 3/4 based on the oil level. Maybe it was just over 3/4 to begin with.

I spoke to my mechanic briefly and he mentioned that in all likelihood that it is my turbochargers that are burning oil. I have about 183,000 km (114,375 miles) on the car.

Will I eventually get boost codes for the turbocharger?
I plan to buy some liquid Moli engine oil saver. Has anyone tried this stuff before for their turbos?

[eljay]

Are your exhaust tips black with signs of oil residue?
The key is finding where the oil is going first before assuming it's the turbos.
Do you see any oil leaks? You can add some approved dye to the oil or change to Liqui Moly Molygen oil that has a dye in it and you can then trace a leak if any.
If there are no leaks and you are seeing consumption, check the vacuum system, intercooler hoses etc. to determine if the oil is present before turbo or on the exhaust side. You or mechanic can use an inspection camera through the O2 sensor hole to check for oil.

[922493]

Boost codes might show up eventually if it gets worse. Moli oil saver? Some like it, some don't. Might be worth a try, but keep an eye on those oil levels and consider a turbo check-up if it keeps chugging oil.

[dieselgg]

Thanks guys for your recommendations. I will mention all this to my mechanic at some point.

I have not noticed any oil leaks on the driveway and nor in the engine bay, but I will check the exhaust tips.

Let's see what happens first with the liqui moly oil saver, which I added last week. Oil level sensor showing full at this point. It's a long shot but for $13 I had to try it.

[lowrydr310]

Originally Posted by dieselgg

I spoke to my mechanic briefly and he mentioned that in all likelihood that it is my turbochargers that are burning oil.

Maybe it's just terminology, but turbochargers won't 'burn oil'. When the internal seals fail they may leak oil into the intake or exhaust, in which case the engine would be smoking.

If you're not smoking, the turbos might still be leaking oil but it could also be a number of other issues. Faulty PCV component somewhere, or even worn piston rings. I wouldn't immediately rush to say the turbos are bad.

Something to consider; I used to have a 325i N52 and sold it to a family member who still has it. The car consumes a quart of oil every 2000 miles or so, but isn't smoking at all. It's been doing this for the past 60K miles and hasn't gotten worse. I replaced the entire PCV system and it didn't change the oil consumption so I'm thinking worn rings or maybe even valve guide seals. Either way the consumption hasn't changed and it's easier to add the quart of oil than to try to fix anything yet.