I had a water pump and timing belt replaced in my car and had to keep going back for a loud squealing noise and while standing there watching the mechanics try and figure out what was wrong , i noticed the engine moving up and down every time they revved it. i pointed that out to them and they told me that my motor mounts were bad. my car was not doing that before i brought it into them, which they'd had for multiple days. we now know that they had subbed the work out to another shop. They are telling us that it is quite common for the motor mounts to fail in hondas and that they wont reimburse us for that. Are they right, is it common for the motor mounts to fail?