C4 check engine light

I had something similar happen with my C4, though I can't remember the exact year. The check engine light kept popping up. Does it seem like it might be related to the throttle body or air supply at all?

Throttle body or air supply, huh? I haven't checked those specifically. What exactly went wrong with yours?

Well, it turned out to be a defective hose connection from the pump to the valve. The mechanic called it a vacuum leak in one of the vacuum hoses. I'd suggest taking it to a workshop and have them check all those hoses; they might have the right tools to diagnose it quickly.

Thanks a lot! I'll get it checked out. Turns out it was exactly what you said – the hose connection. Cost me 175€ to get fixed. Appreciate the help!