DS3 check engine light air valve issue

Hey, I've had a similar issue with my DS3 (though not the same year model). The check engine light illuminated, and it turned out to be a vacuum leak in the air intake system. Check all your vacuum hoses, especially the ones connected to the air valve. If you hear a hissing sound, that's a good indication of a leak. Did you notice any changes in engine performance or fuel consumption?

Thanks for the quick response! I didn't notice any obvious changes in performance or fuel consumption, but I'll definitely check the vacuum hoses more closely. Specifically, which hoses near the air valve should I be focusing on? Any tips on how to identify a small leak?

Okay, if you haven't noticed performance issues, it might be a small leak. Focus on the thinner hoses connecting the air pump to the valve and intake manifold. Gently wiggle them and listen for hissing. Honestly, a smoke test is best, but without the right equipment, it's tricky. Given it's the air valve, a proper diagnosis at a workshop might be the safest bet. I ended up going to a mechanic to fix mine, and it was definitely worth it to avoid causing more damage.

Alright, thanks for the advice. I inspected the hoses as best I could, but couldn't pinpoint the exact location of the leak. I took it to a workshop, and you were right – it was a defective hose connection to the air valve. The repair cost me 175€. Thanks again for your help!