For optimal engine performance engineers have find ways to balance the forces produced by rotational masses and reciprocating masses. If the forces on an engine are not balanced then, certain vibrations are produced that could reduce the longevity of an engine. Using an Internal Combustion Engine Simulator using multiple accelerometers acquired at multiple points along the simulator are used to diagnose any irregularities in the engine by the vibrations measured in the engine. A series of test were carried out on a Four-Cylinder Internal Combustion Engine Simulator under various conditions. The data collected is acquired as the test are carried out in real-time. Since unbalanced forces produce certain vibrations at certain frequencies the data is used to measure such vibrations. The focus of this experiment is correlating a balanced engine operating at normal conditions to engines that have some sort of fault or are unbalanced. The results of this work will provide some insight on dynamic forces acting on engine and how they can affect performance and also show the importance of using simulators to carry out such experiments.