V70 Check Engine Light Air Valve Issue

I had a similar problem with my V70. Do you hear any hissing sounds, particularly after the engine is turned off? Also, has your engine been stalling at all, or do you notice any rough idling? It could indicate a vacuum leak somewhere in the air intake system.

Thanks for the quick reply! I haven't noticed any hissing sounds, but now that you mention it, the engine has stalled a couple of times at traffic lights. Could this really be linked to that air valve hose?

Yes, a defective hose connection from the pump to the valve can absolutely cause those symptoms. The engine stalling and the check engine light are strong indicators. I'd recommend getting a proper diagnosis at a workshop. They will be able to perform a smoke test and check the manifold pressure.

Thanks so much for the advice! I took it to the workshop as you suggested, and it turned out to be exactly what you said – the hose connection was faulty. The repair cost me 175€. All fixed now!