Post-OC oil consumption, BMW N20

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915
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California
This is my 2013 328i with the turbocharged N20 4-cylinder engine and a little over 60,000 miles on it. The engine has been getting M1 0w40 since new. After an oil change, oil consumption gas always been increased for the first 1,200 miles. The engine goes from consuming about 0.7 qt over the first 1,200 miles to consuming just half a quart over the remaining 6,300 miles. This engine has a single turbo, double VANOS, direct injection. I always drive the car about the same. It's not like I take it out to the track and race it for the first 1,200 miles. There's an electronic oil level gauge with min and max marks, 1 quart apart, no conventional dipstick. This behaviour is reliably consistent. What are possible explanations?
 
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pa
do you know that "gauge is CORRECT" + why an 0w oil in california unless its way north + winter!!
 
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1/2 hr N.E. of Detroit
Originally Posted by benjy
do you know that "gauge is CORRECT" + why an 0w oil in california unless its way north + winter!!
That's how we-USAers roll..... 5W in Minnesota, Wisconsin and Yooper Michigan. 0W in Florida, Texas and California. smirk
 

vavavroom

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Originally Posted by ka9mnx
Sounds normal. I don't see anything wrong.
With all my other vehicles, past and present, oil consumption is pretty much consistent, with major increases only due to prolonged high-speed driving, extra load on the engine like when driving in the mountains or when towing. Why would new oil be consumed at a higher rate than oil that's been in use and that has already sheared down a bit?
 

vavavroom

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Originally Posted by benjy
do you know that "gauge is CORRECT" + why an 0w oil in california unless its way north + winter!!
Gauge accuracy seems fine. Let's say half a quart low and I add half a quart it's back to max. Doesn't really matter if it's dead-nuts accurate. It's accurate enough to tell me oil consumption is increased with new oil for the first 1,200 miles. After an oc. 0w40 because you can't go low enough for startup protection and 40 because it's specified for the engine. I also drive the car frequently around Tahoe during skiing season.
 
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10,359
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Colorado Springs
Originally Posted by vavavroom
Originally Posted by benjy
do you know that "gauge is CORRECT" + why an 0w oil in california unless its way north + winter!!
Gauge accuracy seems fine. Let's say half a quart low and I add half a quart it's back to max. Doesn't really matter if it's dead-nuts accurate. It's accurate enough to tell me oil consumption is increased with new oil for the first 1,200 miles. After an oc. 0w40 because you can't go low enough for startup protection and 40 because it's specified for the engine. I also drive the car frequently around Tahoe during skiing season.
1. 0W: Irrelevant in your case. There is no any difference between 5W and 0W in CA temperatures, unless we are talking Tahoe or Yosemite and some freak wether and temperatures below -10 or -20. However, Mobil1 0W40 FS is good oil anyway, and just bcs. it is 0W does not mean you cannot or should not use it. 2. That being said, IMO there are better oils. First of all, I do not like very high sulfated ash number of that oil at 1.32. That is really not good for DI engines and when FS was introduced I was wondering if Mobil1 is trying to address TBN retention with higher SA number. Previous, VISOM version was known to deplete TBN quite fast in DI engines. Castrol 0W40 IMO is more stout oil, Pennzoil Euro L 5W40 is also very stout and still carries LL01 approval. 3. W40 is NOT specified for your engine. For your engine specified are LL01 and LL01FE oils. I personally would never put LL01FE in my BMW. LL01 can be 0W30, 5W30, 0W40 or 5W40. SO grade is irrelevant for your application as long as it is LL01. Now, LL01 is becoming rare, so shooting target should be MB229.5.
 

vavavroom

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I specifically mentioned the car is driven in the Tahoe area during the cold season. I am not interested in this becoming a discussion about my oil choice for this engine unless a plausible correlation to my observation regarding initial post-oc oil consumption can be made.
 
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WA
Regarding increased oil consumption during first 1200 miles and then it tapers off ... I've experienced the same with different cars and/or oils. Oil consumption is higher at first and gradually decreases. Part of it could be due to accumulated fuel dilution which makes it look like less oil is being used ... Just a theory not sure! Drive the card harder (higher rpm) once in a while and see what happens and if you get a more linear oil loss. another theory ... I think the more volatile portion of the oil burns off or evaporates first or quicker and whatever is left is less volatile and the Noack related oil loss decreases over time. i don't think Noack test measures the rate of the oil loss. It just measures the total weight fraction lost over 60 minutes ... As a result, it is possible that portion of oil can evaporate very quickly and then tapers off and the potential non-linearity is not represented with the Noack number. Also some oils could be more susceptible to this!
 
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Maryland USA
Originally Posted by OilUzer
Regarding increased oil consumption during first 1200 miles and then it tapers off ... I've experienced the same with different cars and/or oils. Oil consumption is higher at first and gradually decreases. Part of it could be due to accumulated fuel dilution which makes it look like less oil is being used ... Just a theory not sure! Drive the card harder (higher rpm) once in a while and see what happens and if you get a more linear oil loss. another theory ... I think the more volatile portion of the oil burns off or evaporates first or quicker and whatever is left is less volatile and the Noack related oil loss decreases over time. i don't think Noack test measures the rate of the oil loss. It just measures the total weight fraction lost over 60 minutes ... As a result, it is possible that portion of oil can evaporate very quickly and then tapers off and the potential non-linearity is not represented with the Noack number. Also some oils could be more susceptible to this!
I like this theory- and I think this is how you could test it: Locate a VOA or do your own, then do a UOA at 50% of your OCI. At the oil change do another UOA- and compare the viscosity numbers at all 3 intervals. The 2nd change may show a higher viscosity due to the very light fractions having been consumed, while the last UOA should be about the same as the 2nd. Essentially if you get viscosity that follows the VOA/UOA of low, high, high then you confirmed the theory.
 
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Originally Posted by OilUzer
Regarding increased oil consumption during first 1200 miles and then it tapers off ...
When my Ferrari F355 has a bit too much oil in the dry sump, the engine will consume the extra until the level gets down to 1/2 way mark on the dip stick and then it will not consume a drop for the rest of the OCI. I attribute this to the vapor separator allowing micro-droplets of oil to be sucked into the intake when the oil level is too high and when the oil level gets back down to where it is supposed to be, this phenomenon no longer takes place.
 

vavavroom

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I do UOAs and fuel dilution is not an issue. The oil stays almost in grade after 7,500 miles. It's still a thick xW30 which is fine since the engine calls for 5W30/40. After the next oil change I will not fill it all the way but 0.5 quarts short of max and observe.
 
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Missouri
Not super familiar with the oil level monitor system, but I question the ability to use it to measure tenths of a quart accurately. When the full bar is lit, that just means the level is above the bar below it, not that the it is topped fully to maximum. To actually know where full maximum is, you'd have to trigger an overfill and subtract the amount it took to indicate the overfill that was above the amount that only indicated full.
 

vavavroom

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I know sump capacity I know how much comes out and how much I put in, and I see the corresponding oil level. I know how much I add to keep the oil level at the max mark. While I'm sure a conventional dipstick is superior, even if my calculations are 1/8 of a quart off, I still can tell that oil consumption is initially high and then tapers off rapidly. This trend is irrefutable. Will see what happens if I keep the oil level lower.
 
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Colorado Springs
Originally Posted by vavavroom
I specifically mentioned the car is driven in the Tahoe area during the cold season. I am not interested in this becoming a discussion about my oil choice for this engine unless a plausible correlation to my observation regarding initial post-oc oil consumption can be made.
Only thing that is constant here is your oil choice (well, 2013 M1 0W40 and 2020 M1 0W40 are two different oils). How about you experiment and you try something different just to see whether behavior will be different? Eliminate that possibility, and it is easy one to eliminate. Than if everything stays the same you can go troubleshooting elsewhere.
 
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vavavroom

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Even if M1 from 2013 and current M1 are different, the behavior has not changed. My friend's car with the same engine and different oil displays the same behavior. I doubt it's the oil per se. No troubleshooting will be required since there is no trouble. I'm merely curious.
 
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Originally Posted by vavavroom
Even if M1 from 2013 and current M1 are different, the behavior has not changed. My friend's car with the same engine and different oil displays the same behavior. I doubt it's the oil per se. No troubleshooting will be required since there is no trouble. I'm merely curious.
They are different. 2013 M1 0W40 is VISOM based, current one is GTL based. Performance numbers are vastly different. Current m1 0W40 is more 0W30 in reality. If his vehicle exhibits same exact behavior could be two things: 1. That oil he uses is of same or similar behavior. 2. That that is how N20 behaves. 3. Oil level sensor has that same pattern of behavior when it fails (and those sensors are really not super reliable and they do fail). Since this is not some huge deal like oil consumption on N62 or N63 engines, I would personally start with different oil like Castrol 0W40 or even 0W30 (that oil IMO is best option for Euro engines, but it is pricey). If it continues the same way, then I would look at sensor but after measuring exactly how much comes out. If you rule out sensor, I would say it is behavior of an engine, but that is bit strange behavior.
 
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Missouri
Originally Posted by edyvw
Originally Posted by vavavroom
I specifically mentioned the car is driven in the Tahoe area during the cold season. I am not interested in this becoming a discussion about my oil choice for this engine unless a plausible correlation to my observation regarding initial post-oc oil consumption can be made.
Only thing that is constant here is your oil choice (well, 2013 M1 0W40 and 2020 M1 0W40 are two different oils). How about you experiment and you try something different just to see whether behavior will be different? Eliminate that possibility, and it is easy one to eliminate. Than if everything stays the same you can go troubleshooting elsewhere.
I'd instead just top off as needed and not worry about it. Even though it is a curious appearing phenomenon that the OP would like to understand.
 
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Colorado Springs
Originally Posted by ledslinger
Originally Posted by edyvw
Originally Posted by vavavroom
I specifically mentioned the car is driven in the Tahoe area during the cold season. I am not interested in this becoming a discussion about my oil choice for this engine unless a plausible correlation to my observation regarding initial post-oc oil consumption can be made.
Only thing that is constant here is your oil choice (well, 2013 M1 0W40 and 2020 M1 0W40 are two different oils). How about you experiment and you try something different just to see whether behavior will be different? Eliminate that possibility, and it is easy one to eliminate. Than if everything stays the same you can go troubleshooting elsewhere.
I'd instead just top off as needed and not worry about it. Even though it is a curious appearing phenomenon that the OP would like to understand.
I would actually try to get to bottom of it if it was the case with my car too. I absolutely get it why he is curious.
 
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5,180
Location
Paramount, California
Originally Posted by vavavroom
This is my 2013 328i with the turbocharged N20 4-cylinder engine and a little over 60,000 miles on it. The engine has been getting M1 0w40 since new. After an oil change, oil consumption gas always been increased for the first 1,200 miles. The engine goes from consuming about 0.7 qt over the first 1,200 miles to consuming just half a quart over the remaining 6,300 miles. This engine has a single turbo, double VANOS, direct injection. I always drive the car about the same. It's not like I take it out to the track and race it for the first 1,200 miles. There's an electronic oil level gauge with min and max marks, 1 quart apart, no conventional dipstick. This behaviour is reliably consistent. What are possible explanations?
This is not a real effect. Engines don't consume more oil with fresh oil. You probably have a bad oil-level sensor. My old car's dipstick was nonlinear at the top (showing less oil consumption after an oil change), but these electronic sensors should be precisely calibrated through the software so that they are linear. When the sensor ages, it could give inaccurate readings, particularly near the full level, where the oil level changes slowly, as the oil sumps widen at the top.
 
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