Power Balance Test: Notes
WARNING: This page is about a different car, the 2012 Ford Pickup, 2012 Ford F550 Super Duty, 2012 Ford F450 Super Duty, and 2012 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
The power balance test determines the relative power contribution of each engine cylinder. During the power stroke of each cylinder the test monitors the acceleration of the crankshaft. The crankshaft acceleration is recorded and displayed in firing order for all cylinders. This procedure may be used to assist in diagnosing a low contributing cylinder or injector concern.