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PFI Chart A-4, Power Balance Test

This test checks the performance of each of the cylinders by comparing it to the other cylinders of the engine. The PCM shuts off the fuel a given cylinder in its intake cycle. This measures performance of that cylinder by the amount of RPM drop caused by that cylinder not producing a power stroke.

NOTE: Test numbers refer to test numbers on diagnostic chart.
  1. The engine should be at operating temperature.
  2. Engine RPM drop within 25 RPM.
Fig 1: PFI Chart A-4, Schematic, Power Balance Test
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Fig 2: PFI Flow Chart A-4, Power Balance Test
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