Peugeot 208 Jerking Acceleration

That sounds similar to an issue I had with my 208. Whistling and hissing usually point to a boost leak somewhere in the turbo system. The check engine light is a common indicator. A 'boost leak' refers to the escape of pressurized air from the intake system after the turbocharger, which is why you're experiencing a loss of power. Have you checked all the hoses and connections related to the turbo and air intake?

Yes, I checked the visible connections, but found nothing obvious. Did you have the same stalling and fuel consumption issues?

Yes, the stalling at idle and increased fuel consumption were definitely part of the problem. Because the engine isn't getting the correct air/fuel mixture, it's trying to compensate. Given that you've already checked the accessible connections, it might be worth having it professionally diagnosed. The leak could be somewhere harder to spot without proper tools or diagnostic equipment.

Thanks for the confirmation. It was indeed the boost pressure sensor cable. Replaced it, and the symptoms are gone. Repair cost was 95€.