LEMON Manuals: Even more car manuals for everyone
Home >> Chevrolet >> 2000 >> Tracker 4D Utility, RWD, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System Self-Diagnostics >> Diagnostic Tests >> DTC P0300: Engine Misfire Detected >> Diagnostic Procedures

Diagnostic Procedures

  1. Perform On-Board Diagnostic (OBD) system check. See ON-BOARD DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM. After performing OBD system check, go to next step.
  2. Start engine and observe for a misfire at idle. If a misfire is present, go to step  4. If a misfire is not present, go to next step.
  3. Turn ignition on, with engine off. Using scan tool, clear DTCs. Operate vehicle within FREEZE FRAME conditions. Retrieve DTCs. If this DTC resets, go to next step. If this DTC does not reset, see DIAGNOSTIC AIDS .
  4. Visually and physically check the following items:
    • Improperly operating or leaking PCV valve.
    • Incorrect PCV valve.
    • Vacuum leak at intake manifold or gasket.
    • Vacuum leak at a cracked, split or worn vacuum hose.

    Repair as necessary. After repairs, go to step  18. If no problem(s) exists, go to next step.

  5. Disconnect fuel injector harness connectors. Remove No. 1 ignition coil. Install a spark tester to No. 1 ignition coil spark plug boot. Crank engine while observing spark tester. Repeat procedure for all ignition coils. If any ignition coil indicates a weak spark, go to next step. If spark is okay on all ignition coils, go to step  10.
  6. Check ignition coils and spark plug wires for cracks, terminal corrosion, carbon tracking and moisture. Repair as necessary. After repairs, go to step  18. If ignition coils and spark plug wires are okay, go to next step.
  7. Check ignition wire resistance. Resistance should be 1200-3000 ohms/feet. Replace faulty ignition wire(s). After replacing ignition wire(s), go to step  18. If ignition wire(s) are okay, go to next step.
  8. Check ignition coils for cracks, moisture, faulty electrical connections, carbon tracking or corrosion. Repair as necessary. After repairs, go to step 18. If no problems were found, go to next step.
  9. Replace faulty ignition coil. After replacing ignition coil, go to step  18.
  10. Remove spark plugs. Inspect spark plugs for damage (fouled, cracked, gap, carbon tracking, etc.). Replace as necessary. After repairs, go to step  13. If spark plugs are okay, go to next step.
  11. Turn ignition off. Disconnect fuel injector harness connectors. Connect fuel injector test light to each injector harness connector, one at a time. Observe test light while cranking engine. If test light flashes at each injector, go to next step. If test light did not flash at each injector, diagnose fuel injector circuit. See FUEL SYSTEM in appropriate BASIC DIAGNOSTIC PROCEDURES article.
  12. Check fuel injectors for proper operation. Perform fuel injector coil test and balance test. See FUEL SYSTEM in appropriate BASIC DIAGNOSTIC PROCEDURES article. If a fuel injector is faulty, replace as necessary and go to step  18. If fuel injectors are okay, go to step  14.
  13. If a spark plug is replaced because of fuel, oil or coolant fouling, go to step  15. If a spark plug is not replaced because of fuel, oil or coolant fouling, go to step  18.
  14. Inspect EGR valve for excessive flow or sticking open. Repair as necessary. After repairs, go to step  18. If EGR valve is okay, go to next step.
  15. Check engine for the following mechanical problems:
    • Worn or faulty camshaft.
    • Leaky or sticky valves.
    • Excessive valve deposits.
    • Broken or leaky piston rings.
    • Weak valve springs.
    • Incorrect valve timing.
    • Intake (vacuum) leaks.
    • Leaking head gasket.
    • Loose or broken motor mounts.

    Repair as necessary. After repairs, go to step  18. If no problem exists, go to next step.

  16. Remove CMP sensor. Inspect CMP sensor for damage, foreign material on sensor (magnet) surface, and water or corrosion at connector terminals. Repair as necessary. After repairs, go to step  18. If CMP sensor is okay, go to next step.
  17. Inspect CMP sensor signal rotor in CMP sensor housing for damaged teeth, foreign material, and correct installation. Repair as necessary. After repairs, go to step  18. If CMP sensor signal rotor is okay, see DIAGNOSTIC AIDS .
  18. After repairs, clear DTCs. Operate vehicle within FREEZE FRAME conditions that set DTC. Check for DTCs. If no DTCs are stored, repair is complete. If any DTCs are stored, diagnose DTC(s).
scientia non olet · About LEMON Manuals