I got a Malfunction message while driving back from Hershey Park, Penn yesterday(180miles each way). it stated: REDUCE OIL LEVEL!
I have not added oil to the car.
Or was it stating i need to add oil?
Any ideas?
Bobby

 

I don't know the answer, but one possibility is blowby in the oil. I don't know how MB reads oil level, but if a head gasket went bad or you lost a few rings, coolent or gas could be in the oil. I would say this is a remote chance, but one nonetheless.

Hopefully it was just an errant message that came from a glitch, I have seen that before in all makes of vehicles.

 

I sincerely doubt if the message was caused by a blown headgasket or such. Most likely either your oil was too high as someone added a bit too much or the sensor that detects the level had gone bad. Keep your eye on it and double check the level with the dip stick ot have your dealer do it.

 

As a precaution check the oil level with both procedures. More than likely all will read ok and it may be that the sensor needs to be replaced.

#1
After the motor has been shut off for at least five minutes, but not off so long that the oil is no longer at normal operating temperature, vehicle level:
- key to position 2
- standard display in MFD
- press up or down button engine oil level measuring now

#2
- key to position 1 (if you have been driving, take the key out and reinsert)
- standard display in MFD
- press the trip odometer reset button 3 times
- current battery voltage
- press up button to stats (engine oil level at bottom)
- start engine to register (you will get a more accurate reading by this method with a cold engine)

 

There have been many reports of this problem, and it can be corrected by replacing the oil level sensor. Usually it will occur after you have had a lengthy ride up a moderate grade and will often go out if you then drive on a level stretch for a while. As noted by Konigstiger, you can check it by the alternate, more accurate method, or simple method AFTER the vehicle is stopped and shut off. I doubt that you have a serious problem.

 

I changed the oil in our 03 320 and I did it the old school way by draining it. I did remove the filter AFTER I replaced the oil plug so there is a good possibility that a few (8?) ounces of OLD oil went down into the pan when I broke the vacuum on the filter. Nevertheless, I added exactly 8-1/2 quarts of oil with a graduated cup for the final 1/2 so I can be pretty sure that the car was not overfilled to any serious degree. On extended highway driving the car sends a message about reducing oil level on the MFD. It ususally disappears and reappears several times on a 200 mile trip. When checked at rest at level, it says OK. On the slightest incline it states overfilled. I can only guess that too much is just too much and when the sensor hits the signal point it has no way to say don't panic, I am just slightly overfull. I attribute mine to heat expansion but it could very well be a sensor problem. I have to agree with several people here, just give me the damn dipstick. If I choose to ignore the MFD, at least I can be sure that the sending unit has no discretion and I have no real problem. In the future, I will add only 8 quarts and wait a day or two for the engine oil level to stabilize. I think the mighty V-6 can limp along with only 8 quarts for a little while.

 

What's elevation of that place?

 

Elevation should have nothing to do with this however an incline would as does the volume of the oil when expanded by heat.

 

San Clemente is near sea level.

 

Simple I had some other funny problems reported by MB computer at high elevetion which obviously gone when I returned to the sea level.

 

Thank you for all the responses. This board is awesome!!!! I was driving on a moderately inclining and declining interstate for 122 miles on my trip. Thats probably the reason why the light came on. Today it was fine. No MFD.
Thanks once again!!!
Bobby