Hi, I had a similar problem with my Audi A4 2007 model. I would say I have some experience with cars, but I am not an expert. I took my car to the garage and they found that there were incorrect software values for the fuel pump. We updated the software and the engine has been running smoothly ever since! The whole thing cost me 45 euros. Could you perhaps describe in more detail what your car sounds or feels like when it's giving you problems? Maybe then I can help you more specifically. Hope that helps you!

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Thanks for your answer! My mileage is now 710123 km and the last service was only recently. The symptoms are really variable, it's really hard to describe. When starting cold it sounds like the engine is struggling to start, and then when I drive it feels like the power decreases and then abruptly increases again, especially when I accelerate. Hopefully this will help narrow down the problem. Thanks for your advice!

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No problem, help where you can, right? With the additional info you provided, it almost sounds like the engine is not getting proper air or something is interfering with the fuel flow. Have you had the air filter and fuel filter checked or changed? Given the mileage, something could really be clogged. The spark plugs could also do with checking and possibly replacing. As for the abrupt drop and increase in power, it could also be the throttle body. I hope this helps and good luck with your troubleshooting!

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Hello again! Thanks for the additional advice. I had the fuel and air filters changed at my last service. I haven't had the spark plugs checked yet though. The suggestion about the throttle body sounds pretty sensible too. I think I'll tackle that next. Thanks for your help, your tips were really useful! I'll keep you posted as soon as I have any news.

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