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Home >> Nissan-Datsun >> 1992 >> Sentra SE-R >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/O Codes >> Symptoms >> Symptom Procedure Definition
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Symptom Procedure Definition

The recommended procedures (specified numerically) are interpreted as follows. These steps help determine and rectify the cause of specific symptom.

  1. Ensure fuel pressure is within specification.
  2. Perform appropriate test in INJECTOR MALFUNCTION diagnostic chart in I - SYS/COMP TESTS article. Use DIAGNOSTIC CHARTS DIRECTORY table in I - SYS/COMP TESTS article to locate chart.
  3. Inspect throttle body ports and valves for deposits, wear or plugging. Clean or replace as necessary.
  4. Check for spark using spark tester.
  5. Check idle speed control circuit. See IDLE CONTROL SYSTEM in I - SYS/COMP TESTS article.
  6. Ensure battery and charging system are okay.
  7. Check spark plug for improper gap or fouling.
  8. Ensure there are no vacuum leaks in intake system.
  9. Disconnect oxygen sensor connector(s). Run engine at 2000 RPM for 30 seconds. Return to idle. If idle RPM decreases, repair intake system air leak.
  10. Check EGR control valve operation.
  11. Check EGR control valve solenoid operation.
  12. Ensure engine has adequate compression.
  13. Disconnect exhaust gas sensor connector(s). If symptom is no longer present, check exhaust gas sensor operation. See TESTS W/CODES article.
  14. Disconnect and plug canister purge line. If symptom is no longer present, check purge and vacuum lines.
  15. Disconnect vacuum hose from fuel pressure regulator. If symptom is no longer present, check for vapor-locked fuel.
  16. Disconnect exhaust gas sensor connector(s). Operate engine under no load at 1500-2000 RPM for 30 seconds. If RPM decreases, repair air leak in intake system.
  17. Check ECU harness connector.
  18. Try a known good ECU.
  19. Check ECU power source and ground circuit. See ECU POWER SOURCE & GROUND diagnostic chart in I - SYS/COMP TESTS article. Use DIAGNOSTIC CHARTS DIRECTORY table in I - SYS/COMP TESTS article to locate chart.
  20. Check timing belt for proper installation.
  21. Check throttle linkage operation.
  22. Try a known good airflow meter.
  23. Check for intake valve deposits.
  24. Check engine temperature sensor. See ENGINE (COOLANT) TEMPERATURE SENSOR in I - SYS/COMP TESTS article.
  25. Perform power balance test.
  26. Ensure fast idle cam holds throttle valve open.
  27. With engine idling, disconnect TPS connector (Stanza) or AAC valve connector (all others). If engine RPM does not decrease, check AAC valve circuit. See IDLE CONTROL SYSTEM in I - SYS/COMP TESTS article.
  28. Check exhaust gas sensor operation. See TESTS W/CODES article.
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