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.
3. Engine runs rough. A failing points and condenser system can cause rough running, misfires, lean and rich conditions. If the engine is difficult to start, and runs rough once it does start, then it is time to contact a mechanic to have a look at the system and find out exactly what the problem is.