Talisman Hissing Sound and Fuel Consumption

Hey, I had a similar issue with my Talisman. That hissing sound is a classic symptom. Check the intake hose that connects to the throttle body; they're known to crack and leak. Engine misfire could also be the reason. Is the sound louder when the engine is cold?

Thanks for the tip! Yes, the hissing seems to be louder when the engine is cold. Where exactly is that intake hose located, and is it something I can check myself, or should I just take it to a workshop?

It's usually pretty accessible, near the front of the engine, running from the air filter box. But if you're not comfortable fiddling around, I'd suggest taking it to a workshop. With those symptoms, you probably have a leak there. It could damage the turbocharger if left unfixed. Better safe than sorry!

Thanks a lot for your help! I took it to a workshop, and you were spot on. It was indeed a cracked intake hose. They replaced it for 100€, and now the car runs perfectly. No more hissing, the check engine light is off, and the fuel consumption is back to normal. You saved me a lot of headaches!