[Danderlion]

So I got my F31 about a month ago used. It had 180,000 km on the clock. First thing I noticed when going to get the plates for it, I got a notification about low oil. I added one liter and just chalked it up to heavy driving when test driving at the dealership. Now 1500km later it wants one liter of oil again.

I understand turbo cars tend to drink more than others, twinturbo maybe a bit more, but 1L per 1500km sounds very much doesn't it? No signs of leakage or other warnings.

[AlpineX]

Think about oil coming through the turbos, or the crankcase pressurizing possibly at vcg seals.

[Billfitz]

It's absolutely excessive.

[328iX]

Any smoke out the tail pipe?

[Danderlion]

Originally Posted by 328dX

Any smoke out the tail pipe?

No, that is what surprised me the most. My previous car a volvo v60 2011 D3 had quite a bit of smoke but not a single oil warning for 15000km.

[328iX]

Originally Posted by Danderlion

No, that is what surprised me the most. My previous car a volvo v60 2011 D3 had quite a bit of smoke but not a single oil warning for 15000km.

What's your oil change interval. Probably due to the ridiculous OCI that European drivers have.

With blown turbo seals there's normally a lot of smoke out the tail pipe. It could just be a worn engine/rings

[Billfitz]

Considering it's a diesel if the oil is making its way into the cylinders I wouldn't expect the exhaust to look out of the ordinary, at least not compared to a gas engine.

[Danderlion]

Originally Posted by 328dX

What's your oil change interval. Probably due to the ridiculous OCI that European drivers have.

With blown turbo seals there's normally a lot of smoke out the tail pipe. It could just be a worn engine/rings

Normally I change oil yearly or seasonally depending on if I driven the car hard or not. But as this one is just picked up a month ago and the service in idrive says oil was done right after import I haven't changed it.

[Billfitz]

There's always the possibility that it wasn't completely filled. The service interval reset for an oil change is done via the button on the instrument cluster. iDrive doesn't do a measurement to see if it was filled, and for that matter it doesn't know if the oil was changed or not.

[Danderlion]

Originally Posted by Billfitz

There's always the possibility that it wasn't completely filled. The service interval reset for an oil change is done via the button on the instrument cluster. iDrive doesn't do a measurement to see if it was filled, and for that matter it doesn't know if the oil was changed or not.

That could very well have been the cast when I picked up the car. But as I added a liter, it went about 2/3 to max on the meter and now 1500km later it is at the minimum level as soon as it gets up to temp I would rule that out as my current problem.

I am wondering if it could be a sensor malfunction. I am tempted to get ISTA-D and check the if there are any fault codes as we have long weekend so can't get it checked until tuesday at earliest.

[Billfitz]

The most common sensor problem threads relate to the iDrive not being able to measure the oil level.

[328iX]

Try different brand oils, with Castrol I always burned the least, or you can use an additive to thicken the viscosity

[AlpineX]

Are you confirming with dipstick?
You want to avoid any runaway potential or dpf damage.

IstaD a good choice regardless. Was this a private party sale?

[Danderlion]

Originally Posted by AlpineX

Are you confirming with dipstick?
You want to avoid any runaway potential or dpf damage.

IstaD a good choice regardless. Was this a private party sale?

Wait! Modern bmw has dipstick? I thought all after 2008 was digital only.

[Danderlion]

Originally Posted by AlpineX

Are you confirming with dipstick?
You want to avoid any runaway potential or dpf damage.

IstaD a good choice regardless. Was this a private party sale?

No, it was a dealer sale.

[Danderlion]

Small update. Got ahold of the dealer and had to fight for the extra warranty they sold to include a real BMW workshop and not just some local mom and pops garage.

Book service time for 2nd of May and they will do a "where is the oil going" test (not sure that's the official name). Anyone got any experience with such a test?

[Billfitz]

The usual first step is to use a UV oil dye to check for leaks.

[Danderlion]

They said they would change oil, I then need to drive 1000km and they drain it again to see how much is left and did it leak so that sounds about right then.

[Danderlion]

So my mechanic called me today and asked if I could leave the car over night when I delivered it, they wanted to do some "piston check, so they are not worn out". Sounded odd to me. Is this something that commonly happens before 200k km?

[Billfitz]

Sounds odd to me as well, pistons don't wear out, piston rings do. It would be very unusual to have bad rings that soon with a diesel.

[Danderlion]

Thank you for your input. I will keep a close eye on what they really want to do then. It will be paid by the dealership so not that worried about costs. Would just feel wrong if they went on the try and push for more work than really needed just because they know it's a safe bet to get paid so to say.

[Danderlion]

UPDATE:

I got to the dealership and they drained the engine oil, filled it up (normal bmw twinpower 0-W30), change filter and gave me a spare liter and sent me driving. 1000km to be precise. In that drive the car asked for 1L of more oil and is now sitting at 3/4 meter so it drank 1.25Lish on that 1000km drive. I am now waiting for them to take it in and drain the oil again and see exactly how much is missing.

Things I noticed while doing this 1000km in 3 days drive was that there is no smoke coming out, no noticeable oil leaks (was parked on a white painted garage floor the whole time when standing still over night etc) and it seems to loose power for just a few milliseconds when cruising on the highway. What I mean with that is that it is fast and snappy when actively driving, accelerating, braking, changing gears etc... but after a few minutes after being driving a bit harder and you are now cruising at 120km/h it just very briefly looses power and then reengages. I can best describe it as if you're walking down the street and stumble. That's basically how it feels.

Any wild random ideas what might be going on? The company I bought the car from should be covering repairs but even they have started getting a bit nervous when checking on the progress and started hinting at maybe it would be better for them to replace the car with another from their selection.
I am mostly curious what could be going on as I can't find and similar cases online that would fit with no smoke, no leak and drinking oil and what might the possible costs be to troubleshoot and fix?