Volvo V40 problems

[Jud1974]

I have a Volvo V40 2016 registration and last Friday it just lost all power every time i accelarated. It now won't start and the garage has no idea what the problem is. It's not really showing anything up on diagnostics other than air mass. Any ideas would be helpful if anyone has had the same problem. Thank you for reading.

[PT1984]

What engine? Unplug the air mass. See what happens.