This engine was prone to plug wires being mis routed and shorting on exh. manifolds. With it running spray a mist of water on the wires and see if it develops a miss. Also an over tightened belt will never 'bind" up an engine. Just the opposite, This year of car was noted for the smog pump belt being too loose causing the alternator belt to slip causing weak batteries and misdiagnosed alternator failure! With the engine off, by hand, try to rotate the alternator pulley. If it rotates then the smog pump belt is loose. It must be tightened from under the car. Also a cracked insulator on a spark plug can do this as well. Sometimes holding the brake pedal firmly and slowly adding throttle will produce the miss which helps verify plug wires or cracked spark plug.