Black smoke, check engine light and loss of power: experience with lambda sensor problems on the Audi A3?

Hey, your question reminded me of my own 2014 A4 Audi. Had the exact same problem and the black smoke from the exhaust actually made me really nervous. Went to my garage that I've known for a long time and they did an investigation. It turned out that the lambda sensor was faulty, just as you suspected. It cost me around 375 euros to solve the problem. We had to order the sensor, but since the replacement it has been running like clockwork again. I would recommend going to a garage as you seem to have the same problem. But to be sure, which model is your Audi exactly? That way I might be able to help you more specifically. Hope I could help you despite minimal car knowledge!

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Hey, thanks for your quick reply! It's really helpful to hear that someone had the same problem and was able to get it resolved. My A3 is the 2016 model with a gasoline engine. It's good to know that replacing the lambda sensor helped. I will definitely make an appointment at my garage and have the lambda sensor checked. It's a shame that it's going to cost me, but it's better than driving a jerky car! Thanks again for your help!

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Hey, so this might sound strange, but it seems like you might be right with your assumption about the lambda sensor. I had a similar problem with my 2017 Skoda Octavia diesel. Like you, the check engine light came on and fuel consumption was also high. The mechanic found that the lambda sensor was quite old and no longer in the best condition, so we replaced it - and lo and behold, the problem was solved! The car has been running great ever since. The mechanic explained to me that such an aged lambda sensor can lead to the engine no longer receiving the correct mixture of air and fuel due to inaccurate measurements. This in turn can cause the symptoms you describe. The cost of replacing the lambda sensor wasn't too high for me, you should expect to end up in the region of 200-300 euros, depending on the workshop and any additional work required. I hope this helps you a bit and you get your problem under control soon! Good luck with that!

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Thank you in advance for your answer. Your experience sounds very similar to my problem and gives me hope that the lambda sensor may be the cause. I can totally understand what the mechanic told you. Sounds logical that a faulty lambda sensor can mess up the correct air/fuel mixture and cause symptoms like mine. I will definitely take my Seat Alhambra to the garage and have the lambda sensor checked and replaced if necessary. Your cost estimate sounds reasonable and would be an investment I'm willing to make if it gets the car running normally again. Thank you for the helpful suggestion and I really hope this will solve my problem. I will keep you posted on what comes of it.

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