Mercedes V Klasse Air Valve Issue

My 2021 Mercedes V Klasse, gasoline engine, has started throwing a check engine light. It's got 108563 km on the clock. I've scanned the code, and it seems to point towards an air valve issue. I'm starting to suspect a dodgy hose connection from the pump to the valve. Could this be the culprit? Are vacuum hoses prone to causing vacuum leaks that lead to idle problems? Has anyone else had similar issues with their throttle body or vacuum system?

4 comment(s)

Air valve issue on a V Klasse? Check those vacuum hoses carefully. I had similar check engine light drama. Is the engine idling rough? Could be a vacuum leak like you suspect. I'd check all connections before assuming the worst.

Rough idle sometimes, yeah. Where exactly did you find the vacuum leak on yours? Was it obvious, or did you need to hunt around for it? And did it also trigger the check engine light immediately, or did it take a while?

Mine also caused idle problems. I didn't pinpoint the exact spot myself, honestly. I just took it in. If you're not confident, might be worth getting a mechanic to check it out, especially if it's intermittent. Could save you a headache.

Thanks for the advice! Took your suggestion and went to a workshop. Turns out it was indeed a defective hose connection from the pump to the valve, causing a vacuum leak. Replaced it, and the check engine light is gone! Cost me 175€, but at least it's sorted.

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