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BettinaSchwarzFan

Loss of engine power and unusual symptoms in A4 diesel from 2009

Loss of engine power

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Black smoke from exhaust on acceleration

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Check engine light on

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Jerking on acceleration

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Stalling while idling

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Unsteady engine

Hello everyone, I currently have a problem with my 2009 A4 diesel. It has now done about 149871 km, but on the last trip it started to give up the ghost. The check engine light is on, the engine has lost power and it twitches when accelerating. In addition, it often just stalls when idling and black smoke comes out of the exhaust when accelerating. I think it could be some kind of deviation in the intake volume of the engine. Have any of you had similar problems and how were they dealt with by the mechanic? Unfortunately, I didn't have such a great experience last time, so I'd be happy to hear your experiences and opinions before I go back to the garage. Thank you in advance!

(Translated from German)

4 comment(s)


Jenzerny

Hello, I had a similar problem with my 2012 A6 diesel. The Check Engine light was constantly on and the engine had lost power. The fault code indicated a problem with the timing chain. On closer inspection, it turned out that the fuel pump and the EGR valve were defective. Both ensure that the diesel burns cleanly. But if they're faulty, it can lead to the symptoms you describe: poor performance, jerking, black smoke and a car that shuts off at idle. It was a pretty serious problem and it was quite a job to fix, but afterwards my car was back in top condition. I would definitely recommend taking your car to a garage as soon as possible so that you don't end up with permanent engine damage. Hope this helps a bit!

(Translated from German)

BettinaSchwarzFan (Author)

Hey, thanks for your quick reply. That sounds pretty heavy sometimes, especially when you consider that it can be so many things at the same time. Do you happen to remember how much the whole repair cost you? And has anything else come up since the repair that we haven't discussed here? Thank you!

(Translated from German)

Jenzerny

Hey, you're welcome! So the problem with the deviation in the intake volume of the engine, which you also suspected, was actually also the case with me. But since my last visit to the mechanic it's been fixed, so it's running perfectly again. As for the cost, I had to fork out 155 euros to rectify the fault in the cable connection to the mass air flow sensor and the intake manifold pressure sensor. It was expensive, but my car is running great again and so far nothing new has come up. I hope this makes things a little easier for you and you can get your A4 running again. Greetings back!

(Translated from German)

BettinaSchwarzFan (Author)

Hey, your information really helps! Even if the costs are a bit high, it's worth it in the end. The main thing is that the car runs perfectly again. I will take your suggestion into consideration and take my A4 to the garage as soon as possible. Thanks again for the help and feedback. All the best!

(Translated from German)

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