E46 N42 Oil Consumption

ryanpetit · 21 Dec 2011 at 11:37

Hi,

I've seen a few threats about M54s using a fair bit of oil, is this the case for most BMW petrol engines?

I've put in a litre or 5w-30 per 1500 miles in my 2.0 N42 of late and it's starting to worry me. Is this normal?

Thanks!

[TW]Fox · 21 Dec 2011 at 11:39

I think its only the M54 that has a thirst that warms hearts at Castrol.

ryanpetit · 21 Dec 2011 at 11:42

I was hoping you wouldn't confirm that.

Would faulty valvetronic cause this? It's sounded a little rattly on full throttle a few times in the last week.

mrk · 21 Dec 2011 at 15:53

Any signs of oil leak?

ryanpetit · 21 Dec 2011 at 16:35

Not that I can see, I'm getting paranoid its the crankcase breather thing that seems to be a common issue.

[TW]Fox · 21 Dec 2011 at 17:15

Not the end of the world if its the crankcase breather though, I had mine done and it was only about £120ish in parts and 3-4 hours labour IIRC.

ryanpetit · 21 Dec 2011 at 18:29

Oh ok, not too bad then.

Some of the posts on E46Zone made it sound like a huge deal. Going to take the engine cover off in the light tomorrow and see if there any signs of leaking from around the rocker cover gasket.

[TW]Fox · 21 Dec 2011 at 18:30

It's a massive PITA but you can just pay somebody else to do it for you

I think it cost me £550 inc parts to have the CCV replaced and the VANOS oil seals renewed. Most of that was labour.

brakeinup · 22 Dec 2011 at 10:21

I wouldn't worry about a litre every 1500 miles. If it is not leaking then I believe this is quite common.

My wife has a 2004 E46 320i Sport which consumed oil at an alarming rate (1 litre every 500 miles or so). CCV was checked and needed replacing which was done but only a marginal improvement in oil consumption was gained.

Moving from 5w30 FS to 5w40 FS has vastly improved the oil consumption.

[TW]Fox · 22 Dec 2011 at 10:25

Your wifes car has a completely different engine. As we have already covered, oil usage like this is common on M54 engines such as that in your wifes car, but not on the engine in the ops car.

brakeinup · 22 Dec 2011 at 10:27

Of course. The link is the CCV which could be his issue as mentioned before.

[TW]Fox · 22 Dec 2011 at 10:37

Your point was that you wouldn't worry about a litre every 1500 miles. On your wifes car I wouldn't worry either but I would worry about such consumption on the engine in the op

brakeinup · 22 Dec 2011 at 10:52

Fair comment

It looks like the N42 has its own long list of issues

Good luck Op

mrk · 22 Dec 2011 at 11:53

What long list? I've only encountered some of the common ones but they apply to all model ranges (almost) such as coil pack failure and so on. Had mine 3.5years and the most expensive service bill so far has been coil pack

There was once a coolant leak suspicion but that turned out to be the res cap not being tightened properly so the sealed system wasn't....sealed!

ryanpetit · 22 Dec 2011 at 15:04

So had a good search around today for any signs of a leak and can't see anything. The engine bay itself is pretty clean so fairly confident I haven't missed anything.

From what I am reading about CCV failure, I would see some smoke from the exhaust and there is none so I'm feeling better about that.

Moving from 5w30 FS to 5w40 FS has vastly improved the oil consumption.

I've seen this a number of times now. The inspection 2 is due in 900 miles, I'm thinking I will supply my own 5w40 oil and see how it goes from there.

bigjimmyauk · 22 Dec 2011 at 15:09

IIRC most handbooks say up to 1 litre oil consumption per 1000Km.

Think every engine varies drastically i wouldn't worry too much about 1 litre every 1500 miles. I currently use about 1/2 litre every 2000 miles.

Have you checked the obvious things rocker cover seal, oil filter etc etc

ryanpetit · 22 Dec 2011 at 15:13

bigjimmyauk said:
IIRC most handbooks say up to 1 litre oil consumption per 1000Km.

Think every engine varies drastically i wouldn't worry too much about 1 litre every 1500 miles. I currently use about 1/2 litre every 2000 miles.

Have you checked the obvious things rocker cover seal, oil filter etc etc

Yea checked all of those, even the exhaust manifold to make sure it wasn't dripping on there and burning off.

If it's within the manufactures tolerances then maybe I'm worrying about nothing, just seems like quite a lot...thinking about it 4 litres over 6000 miles is not fair off what the engine takes on a service. Maybe I should skip on oil changes from now on

bigjimmyauk · 22 Dec 2011 at 15:29

ryanpetit said:
Yea checked all of those, even the exhaust manifold to make sure it wasn't dripping on there and burning off.

If it's within the manufactures tolerances then maybe I'm worrying about nothing, just seems like quite a lot...thinking about it 4 litres over 6000 miles is not fair off what the engine takes on a service. Maybe I should skip on oil changes from now on

no because the old oil will still be sitting in the sump and filter and cycling through your engine.Your just basically putting new on top of old then mixing it.

lets say you left half a glass of milk on the side for a week then topped it up with fresh milk would you drink the whole glass lol.

Check your handbook though as they usually state maximum oil consumption.

if your getting anything above that figure i would be concered as usually those figures are massively over inflated compared to actual usage of 99% of the cars.