Peugeot 208 throttle valve issue

Interesting. I had similar symptoms on my 2018 Opel Astra, though it was a diesel. High fuel consumption and struggling to start. Have you checked the accelerator pedal module? On the Astra, a defective module was causing the throttle valve to act erratically, leading to the issues you described.

Thanks for the tip! I haven't checked the accelerator pedal module yet. How did you figure out that was the problem on your Astra? And what exactly was it doing?

Well, on my Astra, a diagnostic tool showed error codes related to the accelerator pedal position sensor. Basically, the sensor was sending incorrect signals to the engine control unit, messing with the air-fuel mixture. The symptoms were nearly identical to yours. Based on my experience, and given your Peugeot's symptoms, it's definitely worth investigating. If you're not comfortable doing it yourself, I'd advise taking it to a workshop to get it checked properly. It's likely not something easily fixed at home.

Thanks for the detailed explanation! I took it to a workshop as you suggested. Turns out, the accelerator pedal module was indeed defective, causing the throttle valve issue. The repair cost me 205€. Hopefully, this solves the problem!