[Cosmos99]

Backgound 2009 E91 328xi with 158k miles. Oil level was dead center for 2k miles since last oil change then dropped 1/4 down. I am not worried about that...Drove it to go snowboarding New Years day and its all uphill for about 75 miles and 6000 ft in elevation. On the way home ( downhill ) it was registering one quart low. I am new to non dipstick cars and I am not sure if it was the severe uphill or downhill that altered the level or does the sensor compensate for that. Got back into town and went to check buy some oil. Checked the car on a level surface the next morning and it was back to dead center which was higher than it was 2k miles ago. Is this "normal" or may I have a blocked oil passage or faulty sensor? The car has been very well maintained by the previous owner.

Thanks,

Ed

[Brian86]

A little fluctuation is normal in mine. I've read that the car compensates for the grade you're driving on but I don't think it's very good at it.

I would continue to monitor for a few more drive cycles to see what it does. Keep some oil in the trunk in case it falls to low-low.

[vester86]

Don’t worry about it and top it up with 1 liter/quart when the car tells you to do so

[Avus95]

Thanks guys! I will continue to monitor it and keep some extra oil on hand.

[mousefarmer]

I've always checked when the car is warm but not hot such as a short drive or after the car has been sitting in the garage cooling down after a long drive but is still warm.

[tcphoto]

I suspect the rapid change in altitude caused false readings, keep a quart of oil in the trunk and monitor it.

[marvinstockman]

Normally, my 328i is parked facing up, one time when it was facing down the driveway (my driveway is fairly steep), it registered one quart low when I started the car. Don't worry about it, and measure it when the road is kind of flat.

Also, your car holds 7 qts, even if your one qt low, you're OK.

[Efthreeoh]

When you say "dead center" what do you mean? The e-dipstick bar graph represents the quantity of just the top (i.e. the 7th quart of oil) in the engine. So a full bar from Min. to Max. means there are 7 quarts in the engine. So does "dead center" mean a full bar from Min. to Max, or does it mean the forward edge of the bar is in the center between Min. and Max?

If the bar is halfway between Min. and Max, then the engine is a half-quart low, so extended periods of uphill or down hill could report an artificial low reading. It's best to take an oil level reading on a relative level surface, just like you would with a mechanical dipstick. Once the ECU establishes an oil level, it is then updated every 20 minutes of continuous engine operation.

Take time to read how the e-dipstick works.

https://www.e90post.com/forums/showthread.php?t=1533444

[Efthreeoh]

Originally Posted by mousefarmer

I've always checked when the car is warm but not hot such as a short drive or after the car has been sitting in the garage cooling down after a long drive but is still warm.

The ECU needs initially at least 5 minutes once the engine oil has reached normal temperature and the car has been driven so the system sees acceleration forward and side to side. If you start the engine cold, then sit with it running until the engine reaches temperature, you'll only get the last oil level the computer recorded. You have to drive the car for the level to update.

[mainbearing]

Sounds normal.

[Cosmos99]

Originally Posted by Efthreeoh

When you say "dead center" what do you mean? The e-dipstick bar graph represents the quantity of just the top (i.e. the 7th quart of oil) in the engine. So a full bar from Min. to Max. means there are 7 quarts in the engine. So does "dead center" mean a full bar from Min. to Max, or does it mean the forward edge of the bar is in the center between Min. and Max?

If the bar is halfway between Min. and Max, then the engine is a half-quart low, so extended periods of uphill or down hill could report an artificial low reading. It's best to take an oil level reading on a relative level surface, just like you would with a mechanical dipstick. Once the ECU establishes an oil level, it is then updated every 20 minutes of continuous engine operation.

Take time to read how the e-dipstick works.



https://www.e90post.com/forums/showthread.php?t=1533444

meant forward edge of the bar was in the center of min and max. I guess my only real concern was that it was 3/4 low for several weeks and then after the mountain drive it went to full quart low. Then when I went to top it off it read 1/2 low. Now its back to 3/4 low. I will read up on the e dipstick. This is my first car with one. After owning 34 cars this is my most modern one after the 2004 R32 and several Z3 M coupes. Thanks for the link.

[Efthreeoh]

Originally Posted by Cosmos99

meant forward edge of the bar was in the center of min and max. I guess my only real concern was that it was 3/4 low for several weeks and then after the mountain drive it went to full quart low. Then when I went to top it off it read 1/2 low. Now its back to 3/4 low. I will read up on the e dipstick. This is my first car with one. After owning 34 cars this is my most modern one after the 2004 R32 and several Z3 M coupes. Thanks for the link.

I posted the link to that thread I published because as a new E9X owner you are not familiar with the E9X e-dipstick and in an effort to prevent you from overfilling the engine oil sump. The reason BMW recommends the owner only top-off the engine oil when the +1qt notification comes up is because the e-dipstick does not give immediate update of the oil level. There are numerous threads/posts on here where owners overfilled the engine because they expected an instant level change result and didn't get one. Its natural to think the "sensor" is bad when the action of adding oil doesn't instantly change the oil level, because using a mechanical dipstick shows an instant change in oil level. I have a friend who blew out the front crank seal on his son's N52 by doing just that, and he is a serious gearhead; he expected an instant update of the oil level.

Why the Mods don't make my Thread a "Sticky" I'll never know.

[marvinstockman]

The whole system is crap, crap, and crappier, and I think it was done so that BMW could completely seal the crankcase for emission purposes. BMW could certainly have given us, besides the dynamic measurement, a static measurement, which I think would make us all feel a lot better.

[feuer]

Oil level displayed vary depending on how fast or slow the oil get to operating temperature. If these times fluctuate so will the oil level displayed.

[TheMidnightNarwhal]

Originally Posted by Efthreeoh

The ECU needs initially at least 5 minutes once the engine oil has reached normal temperature and the car has been driven so the system sees acceleration forward and side to side. If you start the engine cold, then sit with it running until the engine reaches temperature, you'll only get the last oil level the computer recorded. You have to drive the car for the level to update.

Actually, in my car it does not show the last oil level the computer recorded, it actually always show 100% full, even if I get to 1/4 of the e-dipstick, unless maybe the ecu takes another reading right after the engine is fully off... so more oil in pan?

I don't know if anyone else? This has really bugged me.

[Efthreeoh]

Originally Posted by marvinstockman

The whole system is crap, crap, and crappier, and I think it was done so that BMW could completely seal the crankcase for emission purposes. BMW could certainly have given us, besides the dynamic measurement, a static measurement, which I think would make us all feel a lot better.

There is a static measurement. When it says "OK".

[AWDBooSTIn90]

I did some coding to my car. Partly bc I have an Idrive, Combox, & RVC retrofit and that requires VO coding (Vehichle Order/Option Codes). As well as the usual custom coding you would do for all that stuff and misc changes.

One thing I noticed somewhat recently is that my oil level always shows the same full mark on the picture of the dipstick in the CIC screen. As well as checking it thru the OBC on the Gauge Cluster Screen.

Usually, as far as i know, you only check the oil thru the gauge cluster when you have a non-idrive car.
And when you have factory idrive, you only check the oil thru the idrive menus.

What are some signs of a bad oil level sensor or possibly a bad coding setting causing the gauge to always show full?

I change my oil often and I know before I switched to 5w-40 Rotella Syn, i would use Mobil 1 0W-40 oem style oil. OEM Mann Oil Filter. I would usually need a quart in-between a 6-7k mile oil change using the Mobil 1 and the oil level gauge would tell me this and would go down slowly, as expected.

However I did a bunch of coding bc of enabling more Combox related features like BMW Apps which is tricky and takes a few tries of coding settings depending on your year of car.

At the same time i switched to the Rotella 5w-40, so im not sure if it really is doing nwhat I'd hoped and stopped burning off so much and getting hot. Which it did bc it never goes over 220/230f now vs the 250/260f with Mobil 1 0W-40 euro.

I just want to make sure its full. Thats why i agree they should of just added a oil dipstick. To at least the N54 engines, damn bmw! Big mistake imho...

[Welcome to NBA Jam]

Originally Posted by marvinstockman

The whole system is crap, crap, and crappier, and I think it was done so that BMW could completely seal the crankcase for emission purposes. BMW could certainly have given us, besides the dynamic measurement, a static measurement, which I think would make us all feel a lot better.

It does do a static measurement. It takes about 2 minutes when sitting idle to get an actual value. It enters dynamic measurement mode when you drive and will take longer to give you a reading depending on how much latitudinal acceleration you experience.

If you put the key in the ignition position but don't start the car, it will tell you if there's sufficient oil to safely start and run the engine.

[marvinstockman]

Yes, I'm aware of the 'go and no-go' alert, but an actual static level would have been great. Maybe someone could invent a dipstick for BMW! Imagine that, a dipstick!!

If it wasn't for my E90's magic steering and handling, I'd buy a Toyota. Well, maybe not a Toyota, but maybe a Mazda. That said, I did have a 90's Mazda 6 which was called a Japanese car with Ford quality. So true, so true.

[TheMidnightNarwhal]

Originally Posted by Welcome to NBA Jam

It does do a static measurement. It takes about 2 minutes when sitting idle to get an actual value. It enters dynamic measurement mode when you drive and will take longer to give you a reading depending on how much latitudinal acceleration you experience.

If you put the key in the ignition position but don't start the car, it will tell you if there's sufficient oil to safely start and run the engine.

But that idle static measurement is always 100% wrong whether I am 1/4 full or 3/4 full. It always show me 100% full when I do a idle measurement.

Does anyone else experience the same thing as me?

[Welcome to NBA Jam]

Originally Posted by TheMidnightNarwhal

But that idle static measurement is always 100% wrong whether I am 1/4 full or 3/4 full. It always show me 100% full when I do a idle measurement.

Does anyone else experience the same thing as me?

How do you know it's wrong and you're 1/4 or 3/4 full?

[TheMidnightNarwhal]

Originally Posted by Welcome to NBA Jam

How do you know it's wrong and you're 1/4 or 3/4 full?

When the level is calculated dynamically, like highway cruising for 20mins, the level updates to the actual level, at the moment I'm about half full on the dipstick, but every time I idle measure it shows full, even doing it how it says in ISTA/TIS. Also on a level surface. My sensor is also a new sensor from early this year so I'm sure the sensor is fine.