Diagnosis & Repair

For wiring diagram, see Fig 1. For diagnosis and repair using hand-held tester, see Fig 2-Fig 6 . For diagnosis and repair using OBD II scan tool, see Fig 7-Fig 10 . To identify circuits referenced in testing, see appropriate WIRING DIAGRAM under ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS. For vacuum or EVAP hose routing, see VACUUM DIAGRAMS article. For testing of systems or components, see BASIC DIAGNOSTIC PROCEDURES - 4-CYLINDER article or SYSTEM & COMPONENT TESTING - 4-CYLINDER article. For adjustments, see ON-VEHICLE ADJUSTMENTS - 4-CYLINDER article. To check ECM inputs and outputs, see PIN VOLTAGE CHARTS article. For removal and installation of components, see REMOVAL, OVERHAUL & INSTALLATION - 4-CYLINDER article.

Fig 1: DTCs P0300-P0304 Wiring Diagram

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Fig 2: DTCs P0300-P0304 Diagnostic Procedure (Using Hand-Held Tester - Steps 1-4)

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Fig 3: DTCs P0300-P0304 Diagnostic Procedure (Using Hand-Held Tester - Steps 5-7)

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Fig 4: DTCs P0300-P0304 Diagnostic Procedure (Using Hand-Held Tester - Steps 8-10)

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Fig 5: DTCs P0300-P0304 Diagnostic Procedure (Using Hand-Held Tester - Steps 11-17)

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Fig 6: DTCs P0300-P0304 Diagnostic Procedure (Using Hand-Held Tester - Steps 18-19)

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Fig 7: DTCs P0300-P0304 Diagnostic Procedure (Using OBD II Scan Tool - Steps 1-3)

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Fig 8: DTCs P0300-P0304 Diagnostic Procedure (Using OBD II Scan Tool - Steps 4-6)

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Fig 9: DTCs P0300-P0304 Diagnostic Procedure (Using OBD II Scan Tool - Steps 7-9)

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Fig 10: DTCs P0300-P0304 Diagnostic Procedure (Using OBD II Scan Tool - Steps 10-16)

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