Engine Controls - Tests W/Codes - 7.4L: Introduction: Notes
Most engine control problems result from mechanical failures, poor electrical connections or damaged vacuum hoses. Before condemning the computer system, perform checks and inspections covered in appropriate BASIC TESTING article in the ENGINE PERFORMANCE section below. Failure to do so may result in lost diagnostic time.
- BASIC TESTING - GASOLINE (for "C" & "K" Series)
- BASIC TESTING - GASOLINE (For "G" & "P" Series)
If no faults were found while performing BASIC TESTING PROCEDURES, proceed with DIAGNOSTIC PROCEDURE. If no fault codes or only a non-running Code 12 is present and driveability problems exist, proceed to appropriate TESTS W/O CODES article in the ENGINE PERFORMANCE section below for diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.). If only intermittent codes are present, see INTERMITTENTS in appropriate TESTS W/O CODES article in the ENGINE PERFORMANCE section.