[J Roc 328i]

I own a 2011 328i and the oil was changed 2,000 miles ago so I am confident the correct amount of oil is there and fairly fresh. Yesterday the car had read that the level was on the maximum line but today I was driving the car for 1 hour and the whole time it never displayed the level and said it was "measuring the engine oil level". I check for leaks throughout the engine compartment as well as under the vehicle every week and seem to not see any major leaks. Has this happened to anyone else and have any ideas?

[BashShah]

change the level Sensor, it's cheap and easy to do.
but you will need to drain and refill your oil again.

[Efthreeoh]

Step one is get a BMW scan tool and check for trouble codes. Step 2 open the connector and clean it with electrical contact cleaner.

[J Roc 328i]

Originally Posted by Efthreeoh

Step one is get a BMW scan tool and check for trouble codes. Step 2 open the connector and clean it with electrical contact cleaner.

I see you drive an E90 as well. Has this ever happened to you? Do you have links to any other places I can read about this? I haven't been able to find too many people that have been having particularly the same problem.

[J Roc 328i]

Originally Posted by BashShah

change the level Sensor, it's cheap and easy to do.
but you will need to drain and refill your oil again.

That is what I have been thinking to do. Do you by any chance know of any other links that may have the same problem? Most of the other forums and sites I have checked have had more problems with inconsistent readings than not reading at all for a full hour of the vehicle running. It didn't give me a sensor inactive signal its like it was stuck in a measuring sequence.

[BashShah]

This sensor does not per say measure oil, it only senses pressure and then the computer calculates if there is enough oil or not.

just curious, how are you scanning your car, what tool are you using?
if it is not BMW special Diagnostic scanner, then you may not be seeing a code, and no engine check light will be thrown.

I know it is a stupid design, but you gota go through the hopes to see what exactly is causing the issue.
Also, when you drain your new oil, measure it to see if it is actually correct amount.

Good luck.

[Efthreeoh]

Originally Posted by BashShah

This sensor does not per say measure oil, it only senses pressure and then the computer calculates if there is enough oil or not.

just curious, how are you scanning your car, what tool are you using?
if it is not BMW special Diagnostic scanner, then you may not be seeing a code, and no engine check light will be thrown.

I know it is a stupid design, but you gota go through the hopes to see what exactly is causing the issue.
Also, when you drain your new oil, measure it to see if it is actually correct amount.

Good luck.

Okay, so you really don't understand how the oil level sensor works. It actually measures the oil level in the engine and it does it quite accurately.

Rather than rewriting how the oil level senor works read this:

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

The how the oil level sensor works by using capacitance is not new technology. The technology was developed several decades ago in the machine tool industry as an aid for manufacturing plant equipment maintenance. BMW was innovative enough to apply the technology to automobile engines. Electronic oil level sensing is quite useful in engines that use an oil pressure-drive cam adjustment system like BMW's VANOS. The N52 is not BMW's first use of the technology.

[Efthreeoh]

Originally Posted by J Roc 328i

I see you drive an E90 as well. Has this ever happened to you? Do you have links to any other places I can read about this? I haven't been able to find too many people that have been having particularly the same problem.

The sensor operation is quite simple. There are no moving parts in it. Read the link I posted above so you can familiarize yourself with it, which helps with diagnosing the problem. Being the sensor is purely electrical, if it fails, it is an electrical fault, which is why the first step in diagnosis is to scan the car for manufacturer-specific fault codes. You need a BMW-based scan tool to do this. There are numerous scan tools available for BMW, go to the coding subforum to find out what scan tools you can get.

So first off, as you indicated, the last oil change is within 2,000 miles, and you have no major oil leaks, so it is a safe assumption that the oil level is in the safe operating range and will remain as such. This means you have time to get a scan tool and diagnose the issue. The failure can be either in the sensor electronics (very rare) or with the connector (contaminated or damaged), or on the CAN bus circuit that the sensor sends its data over. The alternator, coolant pump, and oil level sensor all communicate on the same CAN bus circuit. There have been several threads on the subject. It could be as simple as the sensor's temperature probe has malfunctioned. The oil needs to be at operating temperature for the sensor to take an oil level reading. Usually the CBS menu brings up an "inactive" notification if the sensor has failed in such a manner.

Have you tried to get a reading since the appearance of the fault?

So I have replaced the oil sensor in my engine, but not for the fault you are experiencing.

[BashShah]

Yup I stand corrected. I don't know how they work.
I don't want to know. I just want to know that it is working or not.

[cliffschum]

My oil level reading has started to fluctuate back and forth between 1/2, 3/4 & Full. Vehicle has 225K, oil only has 6K, but has been in there for ~ 9 months. No codes in Bav Tech, so I'm assuming sensor is ok. Read through all the relevant threads, and am wondering if the oil is so old that it's electrical properties are also fluctuating ?

Fluctuation has only been occurring for last 500 miles.

Happy to change oil early, just not clear if I should ask Indy to replace what is probably a good sensor ?

2006 E90

[Efthreeoh]

Originally Posted by cliffschum

My oil level reading has started to fluctuate back and forth between 1/2, 3/4 & Full. Vehicle has 225K, oil only has 6K, but has been in there for ~ 9 months. No codes in Bav Tech, so I'm assuming sensor is ok. Read through all the relevant threads, and am wondering if the oil is so old that it's electrical properties are also fluctuating ?

Fluctuation has only been occurring for last 500 miles.

Happy to change oil early, just not clear if I should ask Indy to replace what is probably a good sensor ?

2006 E90

Just wait until the +1qt notification appears, then refresh the oil level with 1 single quart of engine oil. Then drive the car for about 20 minutes and then check the oil level.

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

[nardo.n54]

may have to replace it, by dropping the oil pan... yikers

[Efthreeoh]

Originally Posted by nardo.n54

may have to replace it, by dropping the oil pan... yikers

No. It bolts up to the bottom of the oil pan. Just drop the belly pan and it's 3 nuts.

[Phangnga]

Here, am mostly enjoying the process of learning the e83, and especially its N52. The virtual dipstick, in my view, gives false comfort that the oil is ok; actually, the vanos system needs clean oil to operate efficiently. So we are changing our N52 at 3,000 to 5,000 miles and it seems to be keeping the vanos solenoids relatively clean...resulting in smooth idle. I replaced our oil level/quality sensor last month however it is not working yet. Today, I cleaned the connectors' contacts and applied dialetic grease...will see next few weeks if it starts working properly. Also, finally registered and downloaded the Foxwell update for our NT510 Elite bi-directional scanner; for my next trick I will find the specific engine electronics section in the scanner that reports on the oil level/quality sensor.
Estimating 2 to 3 mor years to really learn this 04.2007 e83