A3 from 2003 with increased fuel consumption, strong exhaust odor and illuminated indicator lamp - possible problems with the secondary air valve

Hey, I had about the same problems with my '06 A4 last year. It could be that it really is the secondary air valve. In my case, the valve was defective and definitely needed to be replaced. It was underpowering the entire engine and causing the high fuel consumption. The exhaust smelled really awful, as you say. They were very professional at the garage, although it was a serious problem, they sorted it out pretty quickly. Hope that helps you out. Give us an update on how it goes for you!

(Translated from German)

Hey, thanks for the reply. It's good to know that I'm not the only one with this problem. Can you remember how much the repair cost? And have you had any new problems since the repair or has everything been fine since then?

(Translated from German)

Hey, you're welcome! It cost me €200 to repair the defective secondary air valve. That may sound like a lot at first, but it's really been quiet ever since. So it was worth the money. Since I went to the mechanic, the problem with the faulty control of the secondary air valve has been solved. Since then the engine has been running like clockwork again, no more indicator lights and the fuel consumption and exhaust smell are also back to normal. I hope this helps you and that everything runs just as smoothly for you. Keep us up to date!

(Translated from German)

Many thanks for the quick response! 200 sounds steep at first, but if it solves the problem, it's probably worth it. I will definitely contact a mechanic, maybe he will find the same defect. Hopefully everything will go as smoothly for me. It feels really great to get support here. I'll let you know as soon as I have any news!

(Translated from German)