A method of evaluating a contribution of a cylinder to an engine includes
measuring a first revolutions per minute of the engine during an enabled
state; determining a dwell period of the cylinder; applying a direct
current voltage signal into a negative terminal of an ignition coil of
the engine during the dwell period to disable the cylinder and create a
disabled state; and measuring a second revolutions per minute of the
engine during the disabled state. A system for evaluating a contribution
of a cylinder to an engine includes a first measure module, a determine
module, an apply module, and a second measure module. The first measure
module measures a first revolutions per minute of the engine during an
enabled state. The determine module determines a dwell period of the
cylinder. The apply module applies a direct current voltage signal into a
negative terminal of an ignition coil of the engine during the dwell
period to disable the cylinder and create a disabled state. The second
measure module measures a second revolutions per minute of the engine
during the disabled state.