BMW N57 Diesel Air Mass Faults How To Test & Diagnose Fault codes 290B00 & 290900

BMW Air Mass fault codes can be tricky to diagnose on late model engines and even more so on turbocharged diesel engines. The DME or DDE monitors multiple inputs when testing air mass to determine if the input values are correct. Oftentimes mass air kg per hour data stream values look incorrect, but are normal. This results in replaced hot film mass sensors that did not require replacing and a fault code that returns. In this video, we are going to look at what values are normal and how to test the sensors involved in determining the correct mass air volume. Our subject vehicle today is a BMW X5 F series with a 3.0 liter N57 diesel engine (N57D30O1 / N57D30T1). This vehicle has multiple air mass faults stored and the mass air flow sensor has previously been replaced, which did not remedy the faults. Codes the vehicle had: 290B00 Air mass system: Measured air mass too low 290900 Air mass system: Measured air mass too high During our diagnostic process, we found carbon build-up and we&show you how we did that and where we found it. Our subject vehicle had fault codes for air mass volume too low and air mass volume too high. For these fault codes to set, similar parameters are monitored with slight variances for the specific fault. In our diagnostic test plan, we will combine the tests into one plan in a specific order to determine the root cause of the fault codes. We&step through the tests one at a time, if you discover an issue, remedy the issue before...