Strange oil level readings

[Craig in Alabam]

Hi Folks,

Sorry if this has been discussed already. I did search, I promise!

Anyway, I just did my second oil change on my 128i. After the change the oil level read full. I checked it several times since then (about two weeks ago) and it has read full every time. Today I took the car out and the oil level read about 3/4 of the way down the scale. I only drove about 20 miles total, but the reading was consistent each time I checked. There are no leaks anywhere. This happened on the first oil change, but it only dropped down to about the half way mark, and stayed there until this oil change (about 4,000 miles, I change the oil once a year...).

Anyone else seen this?

Cheers!
Craig

[durpflip]

Originally Posted by Craig in Alabam

Hi Folks,

Sorry if this has been discussed already. I did search, I promise!

Anyway, I just did my second oil change on my 128i. After the change the oil level read full. I checked it several times since then (about two weeks ago) and it has read full every time. Today I took the car out and the oil level read about 3/4 of the way down the scale. I only drove about 20 miles total, but the reading was consistent each time I checked. There are no leaks anywhere. This happened on the first oil change, but it only dropped down to about the half way mark, and stayed there until this oil change (about 4,000 miles, I change the oil once a year...).

Anyone else seen this?

Cheers!
Craig

i'm not sure if you did these already,but i'll mention them anyways. if you did,sorry for haha.

N52s (or any I6 BMW) are prone to oil leaks at numerous points on the engine and if you're like me and never really bought BMWs to begin with, you'll never notice it until your mechanic notices it. it never drips on the ground unless it gets severe because these things have plastic undercarriages... i don't know what freak occurrence would cause an oil leak at below 80 000 mls,but it's always nice to check things like the belts and the oil filter housing to see if they're soaked.

[desertman123]

Continue monitoring it, but I wouldn't worry.

Maybe the level was right on the cusp of showing full. (example) Like for it to read full, it needs to have 6.5qts, and you had 6.45.

IF I REMEMBER CORRENTLY the oil level only shows the last quart, cuz when it reads empty then it tells you to top off with 1qt.

[Craig in Alabam]

Hi Folks,
Thanks for the replies. I'll just keep an eye on it for a while. When I did the oil change, I only put in 6 quarts and then checked it. It showed full and I thought maybe I didn't get all the old oil out. BUT! I did let it drain for about an hour, both on the jacks and lowered, and it wasn't dripping at all when I buttoned it back up. Perhaps it just took a while for the sensor to realize it was low? Still coming to grips with the electronic dipstick. My other bimmers were all older and had real dipsticks.

In the year since my last oil change the oil level moved very little. I added about 1/2 quart in 5,000 miles which I consider pretty good. I'll just carry a quart around with me until it tells me to add some.

Cheers!
Craig

[Olgeezer1]

If you only put in 6 quarts then you're definitely a quart low. These electronic gauges are about useless and as far as I can see only show major fluctuations. In my car a 1/2 qt. diff. doesn't show up at all.

[Dackelone]

Frankly I never trust the e-dip stick gauge until I have driven the car for about an hour or so. When the car has been driven less than an hour or so... I can have a "full" oil level showing, but then after an hour or so... the oil level will show 3/4's full. So I only trust it after a long trip.

When I change the oil I always just pour in 7 liters of oil, even though it takes 6.9 liters(6.5 quarts). I've also noticed that IF I drive the car more than 6K kms(say 10K kms) or IF I drive the engine very hard(high revs and lots of Autobahn runs) the engine will burn some oil. This is why I always try to change my engine oil every 6K kms or less.

Here is an interesting pdf on the "oil condition sensor" ie the oil level sensor.

IF you do lots of short drives(trips) water can dilute the engine oil and cause an improper oil level reading. Also early 1er's '08's & '09's had a bug in the SW, so an updated SW was needed.

The only "real" way of knowing how much oil is in the engine is to do an oil change and "see" what the OCS shows/reads. You just might have a bad sensor.

[Mr Rooty Von Tooty]

With the engine thoroughly warmed up and running at high speed you'll get a different reading than running along at a moderate speed.

As long as I know the engine is sound and not burning oil, I ignore it. When I change the oil, I carefully catch the drain, so I can measure how much came out. From this, I can determine oil consumption and how much to put back in. I find that a refill is around 6.5 qts.

[julienjj]

The reading has to be done at idle standing still on a fully warmed up engine.
These sensors are very precise. We measure the fuel level in airliners the same way.
Just remember they measure a volume and not a mass, therefore subject to a small variation; it's no different than a physical dipstick.

[Mr Rooty Von Tooty]

Originally Posted by julienjj

The reading has to be done at idle standing still on a fully warmed up engine.
These sensors are very precise. We measure the fuel level in airliners the same way.
Just remember they measure a volume and not a mass, therefore subject to a small variation; it's no different than a physical dipstick.

The reading can be done at idle or while driving. The only requirement is the engine has been warmed up. I'd still prefer a dipstick. I understand they don't have any electrical problems.