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7.3L Symptom-To-Diagnostic Flow Chart Menu

NOTE: In the following table, the circuits referred to are found in the TESTS W/CODES - DIESEL article in this section.
7.3L SYMPTOM-TO-DIAGNOSTIC FLOW CHART MENU

Symptom Circuit Test Step Number
Poor idle quality Rolling idle Shifts harshly Poor fuel economy DJ1
Overdrive Cancel Indicator (OCI) lite always off (E4OD only) TC13
Hard Start (cold) *****
Tachometer inoperative (Vehicle with Tachometer) DJ1
4x4 Low Indicator Light Always Off (with harsh shift) (always on with sluggish shift) - E4OD only TC11
Tachometer indicates a low vehicle RPM DJ1