E92 m3 oil decreasing while driving

[azizsf]

Hello

I bought an m3 e92 2008 4 months ago the car was stored for 2 years , i’ve changed the oil and filter but i noticed that the oil is decreasing while driving as shown in the monitor , it was at half and the it decreased little bit and then shows add 1 liter so i parked and added about half liter then the oil level is above the half i drove about 21 km then shown add 1 liter again , i’ve replaced the oil level sensor brand new oem and still decreasing and i replaced head cover gasket and PCV and still the oil decreasing , i haven’t see any leaks and smoke , i used Liqui Moly 10w60.
What could be the causes of oil lost

[Brandoch]

How much oil did you use in the first place?

[M3SQRD]

My guess would have been the oil level sensor but you’ve already replaced it. Clearly you’d see smoke at the rate the oil level is dropping and requesting you add 1 L. I’ve never been a fan of the electric oil level sensor. Damn emissions requirements has eliminated the oil dipstick. I wish I had something to suggest. Sorry and good luck with your search for the problem.

[azizsf]

Originally Posted by Brandoch

How much oil did you use in the first place?

9 liters

[azizsf]

Originally Posted by M3SQRD

My guess would have been the oil level sensor but you’ve already replaced it. Clearly you’d see smoke at the rate the oil level is dropping and requesting you add 1 L. I’ve never been a fan of the electric oil level sensor. Damn emissions requirements has eliminated the oil dipstick. I wish I had something to suggest. Sorry and good luck with your search for the problem.

Thank you

[Theodore2]

Is the engine stock? Has it ever been rebuilt or refreshed?

[azizsf]

Originally Posted by Theodore2

Is the engine stock? Has it ever been rebuilt or refreshed?

The engine is stock , as the previous owner said the engine was rebuilt due to rod bearing issue and replaced everything down there at around 75k km

[BimmerMan33]

If it were me, I would drain the oil, measure & refill. It generally takes 9 quarts without filter change to be at the full mark.
Next, check for excessive smoke from the exhaust. If normal, then I would remove the underbody stiffening plate & check for leaks, I’d doubt however that such a major leak would go unnoticed..
Let us know what you find!

[kyrix1st]

Also check the coolant reservoir and look for oil residue, your head gaskets might be incorrectly installed, causing seepage into the coolant system.

[azizsf]

Originally Posted by BimmerMan33

If it were me, I would drain the oil, measure & refill. It generally takes 9 quarts without filter change to be at the full mark.
Next, check for excessive smoke from the exhaust. If normal, then I would remove the underbody stiffening plate & check for leaks, I’d doubt however that such a major leak would go unnoticed..
Let us know what you find!

I drained the oil and unfortunately i haven’t measured it and I fill it 8.5 liters around 9 quarts , i haven’t see any leaks and no smoke but the car is bit smelly I guess because of the catless exhaust

[azizsf]

Originally Posted by kyrix1st

Also check the coolant reservoir and look for oil residue, your head gaskets might be incorrectly installed, causing seepage into the coolant system.

Thank you , I’ll will check that

[azizsf]

After I drained the oil and fill it with 8.5 liters, i took the car for a long ride to check , at first the oil level was approximately full and then dropped to half and then add 1 liter message, so i shut down the car, on the next day i took the car and drive the oil level was also nearly full and dropped to half after driving around 50 km , my guess is the oil level is good but something happing while driving once the car cool down next morning the oil level is good.
The first image (add 1 liter)
And then the other two images the next day i haven’t add oil.

[kolosy]

an expensive but good thing to do would be to drain it again and confirm how much comes out, just to definitely rule out an actual leak / consumption.

[exVtekGuy]

Seems like a faulty sensor. Did you replace it? If yes, why? If it was replaced by previous owner, probably good to ask that person if possible.

[kyrix1st]

If the sensor used is not a Genuine BMW OE unit, that could cause problems. I've had this happen on other cars, because although Bosch/VDO may look compatible on the outside, it is likely built to different specifications than that of BMW ones. Don't save on these sensors, just use the BMW ones.

[///M Power-Belgium]

Originally Posted by azizsf

After I drained the oil and fill it with 8.5 liters, i took the car for a long ride to check , at first the oil level was approximately full and then dropped to half and then add 1 liter message, so i shut down the car, on the next day i took the car and drive the oil level was also nearly full and dropped to half after driving around 50 km , my guess is the oil level is good but something happing while driving once the car cool down next morning the oil level is good.
The first image (add 1 liter)
And then the other two images the next day i haven’t add oil.

.

[azizsf]

Originally Posted by kyrix1st

If the sensor used is not a Genuine BMW OE unit, that could cause problems. I've had this happen on other cars, because although Bosch/VDO may look compatible on the outside, it is likely built to different specifications than that of BMW ones. Don't save on these sensors, just use the BMW ones.

It’s brand new Genuine BMW oil level sensor

[azizsf]

Originally Posted by ///M Power-Belgium

.

I considered that from the beginning, the car was imported brand new from Saudi Arabia by the previous owner back on 2008, there is a fee if you want to register the car to our local dealership so you can do the maintenance and service with them, so when I bought the car the first thing i did is going to the dealership to do the checkups and services , they told me that i should pay 1000$ to re-register the car because the car haven’t been on their records for two years, if you haven’t brought the car to them for two year you should register it again and paying 1000$ that sounded ridiculous to me im not paying that amount of money for registrations.

[amrazM]

Pull a few plugs out, check for oil on the spark plugs, check for oil in the plenum, seems like it is going somewhere. is the oil filter housing leaking?

[azizsf]

I just had drained the oil and measured it , it was around 8.2 liters without removing the filter( less than 1000 km) , it seems normal no lost oil , and i removed the underbody stiffening plate and no leaks just to double check.

[azizsf]

Originally Posted by amrazM

Pull a few plugs out, check for oil on the spark plugs, check for oil in the plenum, seems like it is going somewhere. is the oil filter housing leaking?

While the oil issue , i did changed the spark plugs recently they were normal no oil aslo the plenum

[baba louey]

I wonder if ISTAD (diagnostic software) can display the signal coming out of the oil level sensor. I have ISTAD but have never dug that deep into it to see if it can display specific outputs. Just a thought.

I agree with you that getting 8.2L drained without removing the filter seems about right.

Baba Louey