The pain will not go away until one of two things happen.
The cracked piece of tooth may break off relieving the pain when pressure is applied to it. When this happens, the tooth can usually be repaired with a crown or a simple filling and the patient (and tooth) lives happily ever after.
The nerve may die as a result of the repeated assaults placed on it by the moving fragment of tooth. When this happens, the pain to pressure may stop, but the dead nerve leaves the patient vulnerable to a dental abscess unless a Root Canal, and subsequent crown are done.