N52B25 Oil Consumption

N52B25 Oil Consumption

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anonymous-user

Original Poster:

54 months

Sunday 27th March 2016
quotequote all
I brought my 2007, E92 325i (2.5) automatic approved used in 2012. It had 43,000 miles on it.
Having been shocked by having the carbon build up in my Audi S3 removed I wanted a port injection engine... I brought my first BMW.

After driving 2800 miles (little traffic as I start work early) it requested a litre of oil. My driving style is moderate and very rarely spirited. The roads are 30/50mph. A large chunk of that being 50 on the North Circular. Journey to work being around 40 minutes. On most weekends it has always seen a motorway drive as we visit family often - sometimes up to 120 miles away.

Where was I? After adding 1 litre it saw me through 1600 miles before requesting another litre. I read up online and came across various articles suggesting more regular oil changes. I started to change oil every 6,000 miles. This meant I would add a litre after 1500-1700 miles. I even tried changing oil at 3,000 mile intervals and once saw 2400 miles before a litre top up was required.

Things progressively got worse. An oil consumption test was commenced through BMW. The car went through a litre in just over 760 miles.

The dealership stated that this was on the cusp of tolerance. The warranty claim was denied. I was advised to investigate out of pocket.

So I did... Different tests. A compression test came up good. Little difference in compression between cyclinders. Sounded promising. Wet compression was also good. There were no leaks. The mileage was 59,000. Valve cover gasket and oil filter housing spotless. Smoke tested too and no issues.

At one point it seemed like there was excess white smoke from the exhaust but this came and went. It was literally a plume at idle but never returned. I have had friends drive behind me with a dash cam and no excessive exhaust gases have been identified under various driving conditions.

The mileage is now 75,000 miles. I continue to get through a litre of oil between oil changes. A litre being requested anywhere from 760-1700 miles. There is no telling so I carry oil and check the electronic dip stick regularly.

The dealership I went to. Mentioning no names... Turned out to be one of the most honest service/sales guy I knew. He told me that investigating it would become expensive and that BMW would not carry out any warranty work on my 8 year old car. Although it has been serviced at this dealership since new. The only independent garages it saw were for the tests. He suggested I try 10w40 oil but I don't think he knew what he was saying. The manual states 0w30 and it has had nothing but that since new. He hinted that I might be accused of over filling when topping it up.

Other than the requirement for oil it is a beautiful car - especially since ditching the run flat tyres. I'm at a loss what the problem could be. The oil separator is not a stand alone serviceable part on mine which is a shame - I don't know if it is that for sure but clutching at straws.

Further research points toward design. The discussions put it down to the inland oil rings being thin and allowing oil to push past them. I think I could be on to something there as the oil is used mostly under load i.e. Car full of passengers on a motorway run always sees the dipstick drop a notch or even two. The same journey alone rarely sees movement on the dipstick. I'm not a mechanic though my knowledge runs out there.

The service/sales guy I spoke with did give me a brilliant suggestion but he doubts very much that it would work. His idea was simple. Start an oil consumption test. Drive around with bags of cement and the likes in the boot... Burn the oil under the 750 miles tolerance and come back in. I'm thinking of giving it a try...

So that is my story and I'm putting it out there for others to reference. If anyone has any advice or information please feel free to add.

Thanks for reading and hope you did not go cross eyed.

helix402

7,859 posts

182 months

Sunday 27th March 2016
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Different engine, similar prob:

http://diaryofanengineer.com/pages/bmw-630i

Just for info your engine needs LL04 oil, availability in various grades, not just 0w30. These include 5w40, 0w40, 5w30 etc.

anonymous-user

Original Poster:

54 months

Sunday 27th March 2016
quotequote all
Wow thanks. Will read that now.
Yes it has always had correctly specified oil as the dealership dealf with the oil changes and that is where I buy the 1 litre bottles from.

Billy_Whizzzz

2,007 posts

143 months

Sunday 27th March 2016
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I have a N52 B30 in an E61.

It is on 90,000 and gets driven hard. It uses about 1 litre every 2000 miles or so... which seems OK ish.

By comparison I also have an S54 engined Z4M (3.2 litres, same age as the E61) and it uses no oil whatsoever... My wife's Allroad 2.7t uses about 1 litre every 1000 miles.


Ben s14a

4 posts

123 months

Sunday 27th March 2016
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I also have a e61 with a N52B30 that uses oil...

I've only owned it for 6 months, just over 5,000 miles and have had to top it up 3 times.

So far between 1800 and 2400 miles per litre.

With these feet

5,728 posts

215 months

Sunday 27th March 2016
quotequote all
Sadly they all like a drink.... mine might be the earlier derivative - '06 325i,but still the same basic design. Im getting around 3000 miles from full to top-up (still waiting for the alert) though I must admit that when I filled it it was not requesting oil, just I wanted to see for myself. The level indicator seems bloody unreliable, went from full,doing 2000 miles, to 1 mark remaining in 300 miles and has sat there currently travelling a further 250. It also takes a bloody age to register the added oil so overfilling is fairly easily done.

Have you any leaks, has the breather system been checked or replaced? Most common is the crankcase breather chucks oil (vapour) into the intake and burns it off.

Edited by With these feet on Sunday 27th March 09:02

nickfrog

21,140 posts

217 months

Sunday 27th March 2016
quotequote all
Super_G said:
Wow thanks. Will read that now.
Yes it has always had correctly specified oil as the dealership dealf with the oil changes and that is where I buy the 1 litre bottles from.
Can I suggest you buy the oil in bulk and NOT from the dealers: will save you a fortune ! The idea of a slightly thicker oil on that mileage makes sense. I had a N53 3.0 and it never used any oil.

cerb4.5lee

30,550 posts

180 months

Sunday 27th March 2016
quotequote all
The N52 in my 330i uses 1 Litre every 2000 miles as well, it is an oil thirsty engine for sure.

JakeT

5,427 posts

120 months

Sunday 27th March 2016
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As an M54 owner that's mad really. Mine sees redline once a journey and has used half a litre over 5k. Is there nothing wrong with CCV systems on these that cause the engines to suck up their own oil?

stevesingo

4,855 posts

222 months

Sunday 27th March 2016
quotequote all
We have an N52-B30 and although we've had it only 3 months and 4k miles, touch wood, no movement on the oil level indicator.

I believe the key to oil usage is how they are run in from new, that is the first 50-100 miles.

There needs to be some load on the rings for them to bed in and this means putting the engine under load, but not high rpm, from new. If there is no pressure the rings work harden and glaze before they conform to the profile of the bore. Most new car owners baby their pride and joy.

The first owner of our 330 was BMW UK, which would suggest that it wasn't babied from new.

E-bmw

9,217 posts

152 months

Sunday 27th March 2016
quotequote all
I have owned all of the M50/2/4 versions over the years & they are either all or nothing.

I have had cars with the same engines from the same model use anything between 0 & 2 litres/1000 miles.

There seems to be no pattern to it IME.

anonymous-user

Original Poster:

54 months

Sunday 27th March 2016
quotequote all
With these feet said:
Sadly they all like a drink.... mine might be the earlier derivative - '06 325i,but still the same basic design. Im getting around 3000 miles from full to top-up (still waiting for the alert) though I must admit that when I filled it it was not requesting oil, just I wanted to see for myself. The level indicator seems bloody unreliable, went from full,doing 2000 miles, to 1 mark remaining in 300 miles and has sat there currently travelling a further 250. It also takes a bloody age to register the added oil so overfilling is fairly easily done.

Have you any leaks, has the breather system been checked or replaced? Most common is the crankcase breather chucks oil (vapour) into the intake and burns it off.

Edited by With these feet on Sunday 27th March 09:02
This is not a stand alone serviceable part on the N52N B25. Mine is a January 2007. Similar to the 2006 like yours. From mid to late 2007 the direct injection variant was introduced.

I replaced my oil condition sensor at 65k miles as it was giving false readings. There was no fault code for it. I had the oil drained out and measured - lucky for me I had not overfilled.

anonymous-user

Original Poster:

54 months

Sunday 27th March 2016
quotequote all
cerb4.5lee said:
The N52 in my 330i uses 1 Litre every 2000 miles as well, it is an oil thirsty engine for sure.
I'm not the only one...

With these feet

5,728 posts

215 months

Sunday 27th March 2016
quotequote all
Well fk me if the oil alert came on today! 2550 miles from full to low. TBH its 4 miles off 100k so i guess that sort of consumption isnt awful. Im going to do an oil change and put perhaps a 10w40 in and see hiw that copes.

swanny71

2,853 posts

209 months

Sunday 27th March 2016
quotequote all
N52B30 here in a 130i.
Never needed to add oil between services (intervals usually about 18k miles), Engines on 124k and I've done 80k of those.

With these feet

5,728 posts

215 months

Sunday 27th March 2016
quotequote all
Super_G said:
This is not a stand alone serviceable part on the N52N B25. Mine is a January 2007. Similar to the 2006 like yours. From mid to late 2007 the direct injection variant was introduced.

I replaced my oil condition sensor at 65k miles as it was giving false readings. There was no fault code for it. I had the oil drained out and measured - lucky for me I had not overfilled.
Alloy or plastic cam cover? Dont the alloy covered engines have replaceable oil traps? Like this>>

http://www.ebay.co.uk/itm/OIL-SEPARATOR-FOR-CRANKC...

Edited by With these feet on Sunday 27th March 22:07

cerb4.5lee

30,550 posts

180 months

Sunday 27th March 2016
quotequote all
swanny71 said:
N52B30 here in a 130i.
Never needed to add oil between services (intervals usually about 18k miles), Engines on 124k and I've done 80k of those.
That's really good going and I got mine(330i)with 48k miles on it and it's now done 64k miles and I've put 8 litres of oil in it.

As someone else mentioned I think whoever ran my car in must have been about 80 years old and just pottered about in it.

sap330

2 posts

99 months

Monday 28th March 2016
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i have an 05 e91 330 and it has nearly 180k miles on it but it only uses 1L between oil changes and i drive it hard most the time, i was expecting it to be worse with that much mileage. i do have a leak from the cam cover as 2 bolts have snapped but haven't got round to fixing it.

tonymor

1,481 posts

172 months

Tuesday 29th March 2016
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I've always been told that most BMW s like oil . Had this conversation before with my very trusty indi .

With these feet

5,728 posts

215 months

Wednesday 4th May 2016
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Thought I'd look at whether my engine has a pcv as the consumption is still higher than I'd like..I had to strip the pollen filter and cover off the bulkhead but found the location of it under the inlet manifold beneath the rear two cylinders. I removed the map sensor and it had oil on it so have ordered the part from eBay and will fit it next week. Looks like a bit of a pain as the inlet manifold will have to come out but should only take a morning.