If the cam chain adjuster was defective and not adjusting, you'd hear a noisey chain.

In the case of a not defective cam chain adjuster doing it's job to the point of the plunger disengaged from the housing, you'd hear a grinding noise from the plunger rubbing against the gears.  Promptly followed by the sound of the piston bashing away at the valves.

If you hear an odd sound coming from your engine, I suggest you figure out what it is before tearing down the freeway 'cause you won't get a second chance.