Expedition Check Engine Light

Sounds familiar. I had a similar check engine light issue with my old 2012 Opel Astra. Turned out to be a vacuum hose problem linked to the throttle body. Was the hose obviously cracked or damaged on yours?

Not that I could see at first glance, no. I wiggled some hoses but haven't found the problem myself. Thinking about it, I didn't check too thoroughly around the air valve though. Was your Astra stalling? How did you find the broken hose?

My Astra wasn't stalling, just idling rough. I eventually had to take it to a workshop; they used a smoke machine to find the leak. Given the symptoms and the mileage of your Expedition, I would recommend the same.

Thanks for the tip! I took it to the workshop just now, and you were right - it was the air valve hose connection. Cost me 175€ to fix. Runs like new now, I appreciate it!