Mike's Workshop Manuals: Service manuals for every vehicle
Home >> Chevrolet >> 1998 >> Camaro SS, 2D Convertible, Standard >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System - System & Component Tests - 5.7L >> Fuel System >> Engine Control System - System & Component Tests - 5.7L >> Fuel Injector Circuit Diagnosis

Fuel Injector Circuit Diagnosis

  1. If powertrain OBD system check has been performed, go to next step. If powertrain OBD system check has not been performed, perform powertrain OBD system check. See POWERTRAIN OBD SYSTEM CHECK in TESTS W/CODES - 5.7L article.
  2. Connect scan tool to data link connector. Start engine and let idle. Using scan tool, monitor MISFIRE CUR. COUNTERS on MISFIRE DATA LIST. If any MISFIRE CUR. COUNTERS are increasing, go to step 4). If no MISFIRE CUR. COUNTERS are increasing, go to next step.
  3. Monitor MISFIRE HIST. COUNTERS on MISFIRE DATA LIST. If any MISFIRE HIST. COUNTERS indicate greater than zero, go to step 17). If all MISFIRE HIST. COUNTERS indicate zero, check for poor connection at fuel injectors and repair as necessary.
  4. Check fuel injector ignition feed fuses. If all injector fuses are okay, go to next step. If any fuel injector fuse(s) are blown, go to step 8).
  5. Turn ignition switch to LOCK position. Disconnect fuel injector harness connector that MISFIRE CUR COUNTER are increasing. Turn ignition switch to RUN position. Using a test light connected to ground, probe ignition feed circuit (Pink wire) at appropriate fuel injector harness connector. If test light illuminates, go to next step. If test light does not illuminate, go to step 10).
  6. Turn ignition switch to LOCK position. Connect fuel injector test light to fuel injector harness connector. Start engine. If test light blinks, go to next step. If test light does not blink, go to step 11)
  7. Check the fuel injector harness terminals for poor connection. If a problem exists, repair as necessary. If a problem does not exist, go to step 15).
  8. Turn ignition switch to LOCK position. Disconnect the 4 fuel injector harness connector related to fuse that was blown. Using a test light connected to battery voltage, probe one fuel injector ignition feed circuit. If test light does not illuminate, go to next step. If test light illuminates, go to step 13).
  9. Measure resistance of each fuel injector that is powered by blown fuse. If resistance is not 11.4 ohms or less at any fuel injector, go to step 14). If resistance is 11.4 or less ohms at any fuel injector, go to step 15).
  10. Repair open in appropriate fuel injector ignition feed circuit (Pink wire).
  11. Turn ignition switch to LOCK position. Disconnect PCM harness connector containing fuel injector control circuits. Check fuel injector control circuits for open, between PCM and fuel injector harness connectors. If open exists, go to next step. If open does not exist, go to step 16).
  12. Repair open in fuel injector control circuit.
  13. Repair short to ground in appropriate fuel injector ignition feed circuit.
  14. Repair intermittent short to ground in appropriate fuel injector ignition feed circuit.
  15. Replace faulty injector(s) as necessary.
  16. Replace PCM.
  17. Inspect appropriate injector circuit for the following: poor connection at injector and PCM, intermittent short to ground and intermittent opens. If problem exist, repair as necessary. If problem does not exist, repair by symptom. See TESTS W/O CODES - 5.7L article.
NOTE: Allow engine to cool down to avoid irregular readings due to "hot soak" fuel boiling. To prevent flooding, the FUEL INJECTOR BALANCE TEST should not be performed more than once without starting and running engine.
NOTE: If injectors are dirty, they should be cleaned using approved injector cleaning procedure before performing FUEL INJECTOR BALANCE TEST.
scientia non olet · About Mike's Workshop Manuals