[julianslowe90]

Originally Posted by nsjames

have you ever serviced the PCV system?

there are plenty of things that don't require an engine rebuild that may contribute to excessive oil consumption.

No I have not serviced the pcv, at the moment my pos decides that I won't even go into the on position (acts like the key isn't there when it is) and doesn't deserve and type of service.

[elons335i]

For anyone following, the car continued consuming oil shortly after the PCV overhaul. I then changed the oil and it’s been about 5,000 miles without consumption; approximately 194,000 on the dash.

[case_manager]

i think its normal for this engine....I add 1 qt every 2000 miles. (133k)

[nsjames]

Originally Posted by case_manager

i think its normal for this engine....I add 1 qt every 2000 miles. (133k)

and I never add oil between 10K mile oil changes.
Lose three quarters of a liter according to the oil sensor.

155K miles.

it's not normal.

[Jesda]

My oil consumption dropped significantly when I replaced the ignition coils (there was an occasional misfire) and replaced the CCV breather.

[gIzzE]

I said it earlier, but why are you guys using 0w30?

The N52 has always been 5w30 or 5w40 then when the miles rack up many move to a slightly thicker grade, like 10w40 or 10w50.

I have another 330i again and with 100k miles on it wouldn't want 0w30 in there.

[vilord]

Originally Posted by ducatiti

Is it true that the more often you change your oil, the more prone we will have oil leaks?

My favorite comment on this thread

If you change your oil less, you will have less oil leaks because you'll need a new car/engine before it leaks

My 150k mile engine was consuming about 1 quart per 5,000 miles. I installed a 3 stage intake, and consumption dropped to 1 quart for the next 10,000, and then dropped to zero quarts as it approached 170k. I thought maybe the oil level sensor was broken, so I had the shop measure at my 170k change, it hadn't lost any.

I'm pretty sure that most of the consumption was from the PCV system that was replaced when I installed the 3IM.

[nsjames]

Originally Posted by gIzzE

I said it earlier, but why are you guys using 0w30?

The N52 has always been 5w30 or 5w40 then when the miles rack up many move to a slightly thicker grade, like 10w40 or 10w50.

I have another 330i again and with 100k miles on it wouldn't want 0w30 in there.

0-30 and 0-40 are both approved for use in colder climates.

I wouldn't run a 50 weight. You'll robably end up with soaring oil temps.

I run 5w40, cause lifter tick.
but I have run 0-40 without issue, and my wife's volvo has been on 0-40 for the last 6 years without issue.

[gIzzE]

The problem with 0w30 is the oil consumption, especially as they get older and you get slight wear to the valves etc.

I think 5w40 is a safer bet on these cars that are using so much oil.

Alpina said 10w50 on N52 based cars at 120000km. There was no mention of temperatures, but I would be more worried about the 10 than the 50 on cold mornings.

[nsjames]

Originally Posted by gIzzE

The problem with 0w30 is the oil consumption, especially as they get older and you get slight wear to the valves etc.

I think 5w40 is a safer bet on these cars that are using so much oil.

Alpina said 10w50 on N52 based cars at 120000km. There was no mention of temperatures, but I would be more worried about the 10 than the 50 on cold mornings.

the problem with going to a heavier oil is that when it gets hot it gets thick, when it gets thick you have more shear, which increases oil temperature even more, resulting in it getting thicker.

0/5/10 probably not a big deal on the cold side.
50, maybe a big deal on the hot side.
There's a pretty big difference between a 30W oil and a 50W oil.
I ran 0-40, 5-30 and finally settled on 5-40 as the best solution for the lifter ticks.
My oil temps are higher with 40w, but not excessively so. below 250.

I'm sure they all provided adequate lubrication to the engine and none of them had excessive consumption.

I would say to all of those with higher mileage n52 that are consuming oil to service the valve cover or CCV system if it's an early one.

[arkie6]

Originally Posted by nsjames

the problem with going to a heavier oil is that when it gets hot it gets thick, when it gets thick you have more shear, which increases oil temperature even more, resulting in it getting thicker...

Neither straight weight nor multi-weight engine oil gets thicker when it gets hot. A 10W-50 at 100 deg C has a lower absolute viscosity, i.e. it is thinner, than it is at 40 deg C. Much thinner. What 10W-50 means is that it performs like a heavy 50 weight oil at 100 deg C (operating temperature) and performs like a light 10 weight oil at 40 deg C. The 10 weight oil at 40 deg C is still much more viscous than 50 weight oil at 100 deg C.

[Angelcma]

My car consumes 1qt every 1.5k miles. Any advice? Car has 75k miles

[vilord]

Your pcv system may be clogged... My old car burned about that much at 130k, and after I swapped the intake (which includes the pcv) with a lower mileage 3 stage, consumption dropped to zero

[Angelcma]

Originally Posted by vilord

Your pcv system may be clogged... My old car burned about that much at 130k, and after I swapped the intake (which includes the pcv) with a lower mileage 3 stage, consumption dropped to zero

Car is an 06, n52 e90 do you know of a diy on how to do it?

[vilord]

This topic over on bimmerfest has some links that may be useful.

For an 06 the ccv is not in the intake.

Other common leak points are oil filter housing gasket, valve cover gasket, oil pan gasket, and rear main seal.
Pcv/ccv is what to check when the oil isn't leaking on the outside of the engine
https://www.bimmerfest.com/forums/sh...d.php?t=934743

[ctuna]

There is a DIY subforum here and many How to videos on ytube
and the net just do a appropriate google search with e90 as part of
the search terms.

[C4maro]

My oil consumption went way down and power way up after replacing vac lines. One turbo wasn't even actuating for like 30000kms unbeknownst to me lol.

The car floats along with a lot less gas needed now.

[Angelcma]

I just changed my ccv system. I will continue to update how my consumption continues. The ccv was indeed really clogged. Also mi valves looked quite dirty so my issue my have something to do with bad valve seals.

[Efthreeoh]

Originally Posted by arkie6

Neither straight weight nor multi-weight engine oil gets thicker when it gets hot. A 10W-50 at 100 deg C has a lower absolute viscosity, i.e. it is thinner, than it is at 40 deg C. Much thinner. What 10W-50 means is that it performs like a heavy 50 weight oil at 100 deg C (operating temperature) and performs like a light 10 weight oil at 40 deg C. The 10 weight oil at 40 deg C is still much more viscous than 50 weight oil at 100 deg C.

This is not correct and is misunderstood by most people. The "W" rating is the measure of the oils ability to "pour" at -40 deg.F/C. 10W means it meets the SAE pour spec at -30 deg F. 5W means it pours at -35 deg. 0 means it pours at -40.

[Angelcma]

This is what mi intake valves looked when I changed the ccv.

[Angelcma]

Okay, changed ccv and car has a strange gurgling sound coming from the intake and also idle is unstable. Feels like car wants to shut down. I Still have the old ccv. I hope this new part isn't defective and it was just bad install

[DgjoX6M2016]

Originally Posted by Angelcma

Okay, changed ccv and car has a strange gurgling sound coming from the intake and also idle is unstable. Feels like car wants to shut down. I Still have the old ccv. I hope this new part isn't defective and it was just bad install

Sounds like a vacuum leak? Something up for sure with your CCV system. Too much carbon building up for PFI.

Here is my N52 after 150k.

Good news is the buildup down on the valves doesn't look too bad. Would not need to walnut blast or anything like that.

Maybe run some good quality detergents at an increased interval after you get it back together. Techron or LiquiMoli.