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Diagnosis & Repair Procedure

NOTE: For better performance and results of this diagnostic procedure, usage of appropriate wiring diagram is recommended. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL.
NOTE: Perform all voltage and resistance tests using a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance, unless stated otherwise in test procedure. Use an ohmmeter to isolate wiring harness shorts or opens.
  1. If engine system check has been performed, go to next step. If engine system check has not been performed, perform A-4: ENGINE SYSTEM CHECK  under SYSTEM TESTS, then go to next step.
  2. Perform ignition system check (spark plugs and ignition spark) referring to SPARK TEST under IGNITION CHECKS in BASIC DIAGNOSTIC PROCEDURES article. If ignition system is okay, go to next step. If ignition system is faulty, repair as necessary and repeat DTC CONFIRMATION TEST  .
  3. Check fuel injectors. See FUEL INJECTORS under FUEL SYSTEM in SYSTEM & COMPONENT TESTING article. If fuel injectors are okay, go to next step. If fuel injectors are faulty, repair as necessary and repeat DTC CONFIRMATION TEST  .
  4. Check system fuel pressure. See FUEL PRESSURE under FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURES article. If fuel pressure is as specified, go to next step. If fuel pressure is not as specified, repair as necessary and repeat DTC CONFIRMATION TEST  .
  5. Perform suspect fuel injector check. See FUEL INJECTORS under FUEL SYSTEM in SYSTEM & COMPONENT TESTING article. If fuel injector is okay, go to next step. If fuel injector is faulty, repair as necessary and repeat DTC CONFIRMATION TEST  .
  6. Perform ignition timing inspection. See IGNITION TIMING in ON-VEHICLE ADJUSTMENTS article. If ignition timing is as specified, go to next step. If ignition timing is not as specified, adjust timing as necessary and repeat DTC CONFIRMATION TEST  .
  7. Perform EGR system inspection. See EXHAUST GAS RECIRCULATION under EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM & COMPONENT TESTING article. If EGR system is operating properly, go to next step. If EGR system is faulty, repair as necessary and repeat DTC CONFIRMATION TEST  .
  8. Check fuel level sensor referring to DTC P0461: FUEL LEVEL SENSOR CIRCUIT - RANGE/PERFORMANCE  . If fuel level sensor is okay, go to next step. If fuel level sensor is faulty, repair as necessary and repeat DTC CONFIRMATION TEST  .
  9. Perform engine mechanical system check. See MECHANICAL INSPECTION under PRELIMINARY INSPECTION in BASIC DIAGNOSTIC PROCEDURES article. If engine mechanical conditions are faulty, repair as necessary and repeat DTC CONFIRMATION TEST  . If engine mechanical conditions are okay, problem is probably intermittent, check ECM, ignition system and fuel injectors for intermittent open or short circuit. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article. After repair, repeat DTC CONFIRMATION TEST  .
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