If your BMW's engine is burning oil, one of the key indicators will be low oil pressure, or a low oil level. Finding out why the car is burning oil can be really time consuming and frustrating. Fortunately, like most modern cars, BMWs are equipped with a onboard diagnostic system that facilitates troubleshooting. By scanning the diagnostic system for errors, you can find out which specific parts of the engine are failing and causing the burnt oil. Unique codes are given for each component that's hooked up to the diagnostic system so once you have obtained the error code, troubleshooting becomes as simple as decoding it.
Find the onboard diagnostic port in your BMW's interior. Inspect the top of your foot well on the driver's side and look for the rectangular female plug that is about two inches wide. It should be marked "OBD" nearby or on its plastic cover, which may or may not be present depending on the model of your BMW.
Connect the OBD II code reader to the diagnostic port and turn your BMW on. If you can, allow the engine to idle; however, if the engine won't start, or if you are afraid to start it due to low oil pressure, you can simply turn on the electronics by twisting the ignition to the second "Accessories" position.
Turn on the OBD II code reader and allow it to scan for error codes. Keep your eye on the display of the code reader and write down any error codes that appear on the display.
Contact your local mechanic or BMW service center to cross-reference the list of error codes and find out what specific components of your BMW's engine are at fault and causing the oil to burn.
