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KHTischFan

Audi A4 Diesel 2009: Problems with engine light, loss of power and increased fuel consumption

Check engine light on

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Loss of engine power

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Jerking on acceleration

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Strong exhaust smell

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Whistling noise

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Loud hissing on acceleration

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Poor fuel economy

Hi community, I'm having a rather tricky problem with my 2009 A4 Audi Diesel. The check engine light is on, I have lost power, the car is jerking when accelerating and there is a loud hissing noise. I also notice a strong exhaust smell, a whistle and the fuel consumption is much higher than normal. Thought this may have something to do with the boost pressure sensor? Have any of you out there had similar symptoms and could give me some tips? I would be particularly interested to know how you have had this fixed in the workshop and what your experiences have been. Many thanks for your help!

(Translated from German)

4 comment(s)


WolfSpeedy

Hello, I had a similar problem with my 2007 A4 Audi diesel some time ago. My turbocharger was defective, not a nice thing in my opinion. I took it to my garage, where the experts checked it and determined that the turbocharger needed to be replaced. It cost me a whopping 1700 euros, but since then it's been running like clockwork again. Can you give us some information about your car? Does it drive differently now or is the performance noticeably lower? I'm not a mechanic, but the more information you can provide, the better I and the rest of the community can help you!

(Translated from German)

KHTischFan (Author)

Hey, thanks for your answer! My A4 is 2009, diesel, and already has 134567 km behind it. As I said, I definitely have less power, especially when accelerating. The car jerks and hisses, and the fuel consumption is higher than usual. It also smells more like exhaust than normal. I will probably have to take it to the garage. Your costs sound pretty hefty, I hope it won't be that expensive for me. Thanks again for your help!

(Translated from German)

BWin2021

I once had the same problem with my 2010 A4. Exactly the same symptoms: engine light, loss of power, rough running... Cost me a lot of nerves too, I tell you! In my case, it was actually the boost pressure sensor, as you suspected. I took the car to the garage and the guys replaced the sensor. And to be honest: I was glad that it was the sensor and not the turbocharger. But don't let it drive you crazy. It could be expensive, but it doesn't have to be. In my case it was quite straightforward, the sensor cost less than 200 euros including installation. And afterwards, the car really did run like a dream again. It's best to have it checked by the professionals. They'll find out for sure. Good luck, hopefully it's just the sensor!

(Translated from German)

KHTischFan (Author)

Hello, 200 euros would of course be much more pleasant than WolfSpeedy. I've already made an appointment at my garage and hope that it's "just" the sensor in the end. Thank you both for your tips and experiences. Hopefully my A4 will be driving as usual again soon! I will keep you up to date.

(Translated from German)

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