Hello, I had similar symptoms with my Citroen DS3 2012, where the secondary air valve broke, which led to increased fuel consumption and a smelly exhaust. In my case, it turned out that the cable and plug connection to the secondary air pump was defective. Something had to be done about it. The fault diagnosis clearly indicated that this was the cause. The repair involved replacing the valve and the connection. Don't worry, it was annoying but not really serious. I was able to leave the garage after a while and my car finally felt normal. Don't forget, when you go to the garage, get them to check it for you. It could very well be your problem.

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Thank you for the helpful tip! Do you remember how much this repair cost you at the time? And did the car continue to run well afterwards or were there any further problems with the secondary air pump or anything similar?

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Hey, no problem, you're welcome! So, the repair for the secondary air valve and the defective cable/connector cost me about €95 at the time. It was really worth a visit and since then my Citroen has been running like a kitten again. Since I've been to the mechanic and the air valve was repaired, I haven't had any further problems. So, relax and make sure they check it out. With the symptoms mentioned, it certainly won't do any harm.

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Great, thanks for the answer and the help! I can definitely live with €95 if it really is the secondary air valve. I was worried that it would be a major repair and put a big strain on my wallet. I'm definitely reassured about that. I'll go to the garage first thing in the morning and have them have a look at it. Hopefully I won't have any more problems after that and the car will run like an A again. Thanks again and have a nice day!

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