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Home >> Ford >> 2003 >> Excursion 7.3 F, 4WD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System & Component Testing - 7.3L Diesel >> Engine Performance Diagnostic Procedures >> Test 12: Cylinder Contribution Test >> Purpose
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Test 12: Cylinder Contribution Test: Purpose

This test is performed on individual cylinders and injectors to determine if all are contributing equally to engine performance.

NOTE: Only California vehicles will set a Continuous Misfire DTC. Both 49-state and California vehicles will set a KOER Cylinder Contribution Self Test code for a low or non-contributing cylinder. If any CCT or misfire DTCs are set, See TEST NA: INJECTOR DRIVE CIRCUIT OPERATION under SYSTEM TESTS in SELF-DIAGNOSTICS - 7.3L DIESEL article to diagnose the fault.