Skoda Kodiaq gasoline engine power loss and whistling noise

Sounds like it could be a turbo issue. That whistling and hissing under acceleration is a common sign. The check engine light and loss of power definitely point to some kind of problem with boost control. Does the noise get worse when the engine is under load? Have you checked for any obvious leaks in the intake pipes?

Leaks, hmm... where would I even start looking? And how can a valve cause all these problems at once? It's like a chain reaction of bad stuff!

Yeah, a faulty valve can definitely cause all those symptoms. Think of it like a kink in a hose – it messes up the whole system. The hissing is probably boost pressure escaping. If it's the electrical bypass valve, that's part of the turbocharger boost control system. Honestly, with all those signs, it's probably best to get it checked by a professional. Trying to diagnose turbo issues without the right tools can be a pain.

Just letting you know, the shop confirmed it was the electrical bypass valve, like you said. New one installed, cost 250€. Runs like a dream now. Thanks for the help!