Hi, I recently had a similar problem with my 2017 BMW 3 Series diesel. I don't have much automotive knowledge, but I can share my experience with you: My car was also consuming too much fuel and the check engine light was constantly on. In my case, the cause was 'cable/connector secondary air valve/secondary air pump defective'. It cost my garage 95 euros to fix this problem. The guys did a great job and were able to solve the problem. I hope this helps you. Can you tell me more about your car? Maybe then I can help you better. What size engine does it have? Have you ever read the fault memory? The more information you give me, the more I can help you.

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Thanks for your quick reply! My Bimmer has an engine with a displacement of 2 liters. At the last service, 21546km ago, everything was still in order, but I haven't read out an error code yet. That could be helpful, of course! I'll look into that. Maybe I can solve the problem myself, otherwise it's off to the workshop. I like my old car, but sometimes it makes my life difficult. Thanks a million already, I hope I can fix it.

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No problem, buddy! Hmm, with 2 liters of displacement, several things could actually play a role. But it does sound like a problem with the air valve or the cables/plugs connected to it. By reading out the fault memory, you could determine whether the air valve is really the cause or whether it could be something else. Even if you can do this diagnosis yourself, I personally would always be cautious when it comes to engine problems. That's why I suggest, as you said, taking the Bimmer to the garage if reading the fault memory doesn't show anything concrete. And believe me, I know the feeling, I love my BMW, but it can be a pain sometimes. Let me know when you've found the fault. Maybe we'll both learn something new. I'll keep my fingers crossed that you can solve the problem quickly! Keep me up to date.

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Thanks for the tip, buddy! Reading out the fault memory is a good idea. I'll give that a try and see if I can narrow down the problem better. And you're right, especially when it comes to engine problems, it's probably better to play it safe and take the car to the garage. Well, you love them, the old cars, but they just wouldn't be themselves without quirks. I'll let you know if I find out anything new. And thanks again for your help, that really helped me!

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