Definition of quantal. 1  1 [Latin quanti how many, plural of quantus] : of, relating to, or having only two experimental alternatives (such as dead or alive, all or none) 2  2 [quantum] : of or relating to a quantum.
3. Engine movement. Another symptom of bad or failing engine mounts is an engine that moves in the engine bay. If the engine mounts are in good condition, they should be able to secure the engine firmly in the engine bay.
How to tell if a motor mount is bad. How to check loose or bad motor engine mount. Learn the main methods for diagnosing a bad motor mount or bad transmission mount.The first method is to watch the engine as it goes in and out of gear. The next method is to drive the car (when you know it is aligned properly) and see if it pulls.ow to check loose or bad motor engine mount. Learn the main methods for diagnosing a bad motor mount or bad transmission mount.