How to Diagnose and Fix BMW 335i Error Codes P0100, P15B9, P152B, and P150B?

It sounds like you're dealing with a few different issues with your BMW, and I can help you navigate them. For the first code, `P0100`, which relates to the mass air flow (MAF) sensor, it’s often just a matter of cleaning it. Use a MAF sensor cleaner to remove any dirt or debris, and don’t forget to check the air filter as well—replacing it can sometimes resolve the issue. After cleaning, reset the code and see if it comes back. Moving on to the second code, `P15B9`, this indicates a potential leak in the check valve between the intake manifold and the brake booster. You should inspect for any vacuum leaks in that area, as they can lead to performance issues. If you find a leak, replacing the faulty component will likely be necessary. For the third code, `P152B`, it suggests there might be an electrical issue affecting the fuel volume regulator. This can be a bit tricky, but if you notice any irregularities with the spark color—ideally, it should be a light tan—then you might need to replace the sensor. Additionally, check for any large air leaks near the oxygen sensors, as they can cause a lean fuel mixture. Regarding the `P150B` code, which indicates a malfunction in the ignition coil circuit, you might want to look for air leaks in the exhaust system or check the fuel quality, as high sulfur content can clog the diesel particulate filter (DPF). Lastly, for the `P1505` and `P152A` codes, these relate to the idle speed control valve and vehicle speed sensor, respectively. If you’re experiencing issues with idle speed, cleaning or replacing the idle speed control valve might help. As for the speed sensor, if you suspect it’s faulty, replacing it could resolve any performance issues. Start with cleaning the MAF sensor and throttle body, as these can significantly impact your vehicle's performance. If you're comfortable, consider replacing the oxygen sensors as well, since they often fail in pairs. This approach should set you on the right path without needing to rely heavily on mechanics. Good luck with your troubleshooting!