[mrbensam]

So I've had a 330d for about a month now. I got it serviced the first few days I had it at a BM Specialist. Since then it has consumed 5 whole litres of oil in just 2000 miles!!!!!

I always verify with the dipstick before topping up so it's not a sensor issue. The BM specialist had a look for free and couldn't find the issue. They said they checked the boost pipes and intercooler, checked the turbo for play and found no evidence of burning oil from the turbo back.

There is absolutely zero leaks as well. They basically said keep driving it, until it gets worse but I'm not really happy with that tbh. The oil has to be going somewhere??

Has anyone got any idea what might be happening here?? Thanks.

Funny thing is this is supposed to be the most reliable engine and somehow I've bought a stinker hahaha

Edit: I've also had it scanned with ISTA and a code keeps coming back for the pre cat 02 sensor - 287100 - 287500
Also, bimmerlink will not show oil temp for some reason, although the oil temp gauge on the cluster seems to be working

[TurboWeasel]

It's either blowing past the turbine wheel into the DPF/Cat, or the engine is burning it.

Given what you've said/had checked, it can't be anything else.

The O2 sensor is probably oil fouled.

Much blue/white smoke out the back? Cats and DPFs can absorb a lot of it, so modern oil burners don't tend to be fog machines anymore.

Next steps would be to check the turbo and compression/leak down test the engine. As in take off the DPF and check the turbine housing for evidence of oil.

They are reliable. A few bad eggs doesn't mean the entire batch is bad. You haven't mentioned it's mileage or it's history.

There are a few oil temp channels to choose from in Bimmerlink. Did you pick the right one?

[mrbensam]

Originally Posted by TurboWeasel

It's either blowing past the turbine wheel into the DPF/Cat, or the engine is burning it.

Given what you've said/had checked, it can't be anything else.

The O2 sensor is probably oil fouled.

Much blue/white smoke out the back? Cats and DPFs can absorb a lot of it, so modern oil burners don't tend to be fog machines anymore.

Next steps would be to check the turbo and compression/leak down test the engine. As in take off the DPF and check the turbine housing for evidence of oil.

They are reliable. A few bad eggs doesn't mean the entire batch is bad. You haven't mentioned it's mileage or it's history.

There are a few oil temp channels to choose from in Bimmerlink. Did you pick the right one?

No smoke out the back at all weirdly, they said they had a camera on the DPF and couldn't see anything out of the ordinary.

Its got 100k miles and it has BMW service history but he only got it serviced every 20k miles which is obviously way too long between services.

I've tried all the oil temp things I could see in BimmerLink, whats the right one called? Thanks for the reply

[bishbosh]

The PCV valve might have failed, costs about £20 to replace but you'll have to buy an aftermarket part. You can't really check it as the tabs on the cap will break. The replacement comes with a new cap.

For the turbo, take off the pipe between the turbo and intercooler and check if excessive oil is present. Could be leaking past the bearings. Could also check for excessive play in the compressor shaft.

I have a 335d and use 1 litre of oil every 4400 miles.

[MY340i]

Did you buy privately or from a dealer/trader?

[mrbensam]

Originally Posted by MY340i

Did you buy privately or from a dealer/trader?

Privately mate, the half empty bottle of oil in the boot should have been a red flag haha

[mrbensam]

Originally Posted by bishbosh

The PCV valve might have failed, costs about £20 to replace but you'll have to buy an aftermarket part. You can't really check it as the tabs on the cap will break. The replacement comes with a new cap.

For the turbo, take off the pipe between the turbo and intercooler and check if excessive oil is present. Could be leaking past the bearings. Could also check for excessive play in the compressor shaft.

I have a 335d and use 1 litre of oil every 4400 miles.

Thanks mate, isn't the PCV inside the rocker cover on these engines?

BM specialist said there was no play in the turbo

[bishbosh]

Originally Posted by mrbensam

Thanks mate, isn't the PCV inside the rocker cover on these engines?

Yes, BMW would replace the whole rocker cover, but you can buy the PCV valve separately.

[mrbensam]

Originally Posted by bishbosh

Yes, BMW would replace the whole rocker cover, but you can buy the PCV valve separately.

Ahh nice one, do you need to remove the rocker cover to replace it ?

[bishbosh]

Originally Posted by mrbensam

Ahh nice one, do you need to remove the rocker cover to replace it ?

Not at all. I think I removed the intake pipe to get to the PCV valve but that's about it.

[TurboWeasel]

Originally Posted by mrbensam

No smoke out the back at all weirdly, they said they had a camera on the DPF and couldn't see anything out of the ordinary.

Its got 100k miles and it has BMW service history but he only got it serviced every 20k miles which is obviously way too long between services.

I've tried all the oil temp things I could see in BimmerLink, whats the right one called? Thanks for the reply

I'm sure it was called "Oil temp at the sump" or something along those lines, it's been a while since I used it.

Good shout on the PCV, although your guys would have flagged that as the compressor housing, boost pipes and intercooler would all be absolutely full of oil.

5 litres over 2000 miles is insane. Really bizarre there is no evidence by way of oil pooling in the boost path, leaks or smoke!!

[Watsey]

Originally Posted by TurboWeasel

It's either blowing past the turbine wheel into the DPF/Cat, or the engine is burning it.

Given what you've said/had checked, it can't be anything else.

The O2 sensor is probably oil fouled.

Much blue/white smoke out the back? Cats and DPFs can absorb a lot of it, so modern oil burners don't tend to be fog machines anymore.

Next steps would be to check the turbo and compression/leak down test the engine. As in take off the DPF and check the turbine housing for evidence of oil.

They are reliable. A few bad eggs doesn't mean the entire batch is bad.

As per this….get the turbo checked properly.

My 30d used zero oil until the turbo started leaking oil (~95K miles), coincidentally from the hot and cold side simultaneously, and then it suddenly started consuming at a rate of around 1L / 500 miles. Zero smoke. The seals had developed too much tolerance (technically they are oil flingers, not an oil-tight seal), allowing oil to bypass them.

New OEM turbo, zero oil consumption once again.

[mrbensam]

Originally Posted by Watsey

As per this….get the turbo checked properly.

My 30d used zero oil until the turbo started leaking oil (~95K miles), coincidentally from the hot and cold side simultaneously, and then it suddenly started consuming at a rate of around 1L / 500 miles. Zero smoke. The seals had developed too much tolerance (technically they are oil flingers, not an oil-tight seal), allowing oil to bypass them.

New OEM turbo, zero oil consumption once again.

That’s exactly what mines using tbf a litre every 4-500 miles so it would make sense

[Watsey]

Originally Posted by mrbensam

That’s exactly what mines using tbf a litre every 4-500 miles so it would make sense

Get the garage to remove the undertray, and the hot and cold connections to the turbo (DPF and boost pipe) then start the engine and let it idle at full operating temperature.

My turbo was leaking to the extent that oil was steadily dripping on to the workshop floor even though there was no play/float in the turbo shaft bearing.

[V330d]

my car was using similar levels and ended with an engine rebuild

[mrbensam]

Originally Posted by V330d

my car was using similar levels and ended with an engine rebuild

Hopefully don’t end up like you haha, what was gone on your engine?

[SkyJawa]

Originally Posted by bishbosh

I have a 335d and use 1 litre of oil every 4400 miles.

My remapped 335d never needed any oil between services......

[mrbensam]

Originally Posted by V330d

my car was using similar levels and ended with an engine rebuild

And how much did you pay for your engine rebuild??

[V330d]

Cylinder 5, showed wear no further details. I had a leaking EGR cooler and coked manifold prior so maybe this was the cause.
Hasn't used any oil since and over 190k now

[V330d]

Originally Posted by mrbensam

And how much did you pay for your engine rebuild??

£250, excess on insured warranty!!

they first did the rocker cover gasket. I knew this wasn't causing the oil use so persisted and stuck to the line that their first attempt to deal with the oil use hasn't worked. Took a while, total warranty cost of almost 14k.

[lethbridge]

In my experience and as others have said 30d/35d engines really shouldn’t need topping up between oil changes (which will be every 18-20k miles if you do high mileage i.e. lots of motorway plugging). Some owners do go for interim changes but I really don’t see the point when BMW and oil makers have spent years developing the long life oils our engines use. I ran these engines from 2003-2018 ranging from 70k-115k miles on each and didn’t need to add a drop. Obviously they will start to use a nominal amount as they age beyond these sorts of mileages but it shouldn’t be much at all. It really does sound like turbo seals to me and pretty easy to check for the losses you are experiencing.

BMW petrol engines do drink some oil but even my M3 (now on 50k) only needs a 1ltr top up at 9k miles between oil changes at 18k…

Hope you get it sorted…

[Stainy]

Originally Posted by lethbridge

Some owners do go for interim changes but I really don’t see the point when BMW and oil makers have spent years developing the long life oils our engines use.

BMW sell to fleet and want to please fleet managers. They aren't interested in cars beyond about 3 years old. Oil manufacturers want to sell to car manufacturers, so do what they're told.

Most ENGINEERS say every 3-4k you should be changing oil.

If you're getting rid after 3 years you'll probably see no difference - someone else will get your worn car.

I'm not - I'm going with the engineers advice

Some Top Engine Designers say 2k miles!