BMW 4 Series Convertible problems with misfiring for some time now

Hello. I had codes for O2 sensor, MAF sensor and vanos exhaust sensor and engine light on. I changed O2, MAF sensors and had no problem the ECU saw the changing and the codes disappeared. But when I changed exhaust's sensor with both vanos , I experienced rough idle, engine was shaking too much and barely on. I changed all 4 spark plugs and ignition coils and still the same. I also have codes for misfiring cylinder 1 and 4 for vanos exhaust sensor even if I changed it.

Hi I’ve changed spark plug and coil pack but still misfire in the morning but if I unplug the mass air flow sensor and start the car no misfires please note that I have change the mass air flow sensor with the genuine old one from another car

If the misfires stop when you unplug the mass air flow sensor, it's possible that the sensor you installed, even though it's a genuine part, might be faulty or not compatible with your specific vehicle. I would recommend trying a new mass air flow sensor. If the problem persists, it might be best to have a mechanic inspect your vehicle.

I’ve ordered a brand new mass air flow sensor let’s see how it goes and I went to the garage before I changed spark plugs and coil he told me to change them but didn’t work but i did the same thing 3-4 days no misfires if mass air flow sensor unplugged I think it could be the mass sensor

Hello, What kind of vehicle do you have? If you have a vehicle with direct injection, I unfortunately suspect that the injectors in your vehicle are defective and need to be replaced.

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Hello, So if I understand you correctly, you also have this error code on other cylinders, not just the 5th cylinder? Can you also perceive that the engine is running unevenly or that you can hear any exhausts from the engine?

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I have a BMW 116i 2007 e87. Not sure if it is direct injection. I thought of injectors but before I changed the vanos there were no misfiring and rough idle. Why now?

It's possible that the issue with the Vanos system was masking the injector issue, or the problem with the injectors developed after you replaced the Vanos. If the misfires started after the Vanos replacement, it's also possible that there could be an issue with the installation. I would recommend double-checking the Vanos installation and if everything seems fine, then it might be worth investigating the fuel injectors.

Thank you very much for answering. Anither question is that I checked spark plugs (old ones) and they all have coal on the pin. If it was the fuel injectors, shouldn't be clean the s.plugs that fuel injectors not working properly?

The presence of carbon deposits on the spark plugs could indicate a rich fuel mixture, which might suggest that the fuel injectors are delivering too much fuel. However, it could also be a result of other issues, such as a faulty oxygen sensor or a problem with the ignition system. If the spark plugs are heavily coated with carbon, it might be worth replacing them and seeing if the issue persists. If it does, then further investigation into the fuel system may be necessary.