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Basic Inspection: Q45

  1. Check service records for any recent repairs that may indicate a related problem, or a current need for scheduled maintenance. Check the following:
    • Harness connectors for improper connections.
    • Wiring harness for pinches and cuts.
    • Vacuum hoses for splits, kinks and improper connections.
    • Hoses and ducts for leaks.
    • Air filter for clogging.
    • Ensure electrical or mechanical loads are not applied.
    • Ensure headlights, A/C and rear window defogger are turned off.
    • Ensure steering wheel is in straight-ahead position.
    Start engine and warm until coolant temperature gauge is pointing to middle of gauge. Ensure engine speed is less than 1000 RPM. Hold engine speed at 2000 RPM for about 2 minutes. Using scan tool, ensure no DTCs are set. If problem is found, repair as necessary. If problem is not found, go to next step.
  2. Run engine at about 2000 RPM for about 2 minutes under no load. Quickly increase engine speed to 2000-3000 RPM 2 or 3 times. Let engine idle for about one minute. Check idle speed. Idle speed should be 600-700 RPM with transmission in Park or Neutral. If idle speed is as specified, go to step  10. If idle speed is not as specified, go to next step.
  3. Turn engine off. Perform Throttle Valve Closed Position Learning. See appropriate SELF-DIAGNOSTICS article. Go to next step.
  4. Perform Idle Air Volume Learning. See appropriate SELF-DIAGNOSTICS article. If result is complete, go to next step. If result is incomplete, repair as necessary, then go to step  5.
  5. Start engine and warm to normal operating temperature. Check idle speed. Idle speed should be 600-700 RPM with transmission in Park or Neutral. If idle speed is as specified, go to step  9. If idle speed is not as specified, go to next step.
  6. Check the following:
    • Check CMP sensor (PHASE) and circuit. See DTC P0340: CAMSHAFT POSITION SENSOR (PHASE) under DIAGNOSTIC TESTS in appropriate SELF-DIAGNOSTICS article.
    • Check CKP sensor (POS) and circuit. See DTC P0335 OR P1336: CRANKSHAFT POSITION SENSOR (POS)under DIAGNOSTIC TESTS in appropriate SELF-DIAGNOSTICS article.

    If problem is found, repair as necessary, then go to step  5. If problem is not found, go to next step.

  7. Substitute a known-good ECM to check ECM function. Go to step  5.
  8. Check ignition timing at idle with a timing light. Ignition timing should be 12-22 degrees BTDC with transmission in Park or Neutral. If ignition timing is as specified, basic inspection is complete. If ignition timing is not as specified, go to next step.
  9. Turn engine off. Perform Throttle Valve Closed Position Learning. See appropriate SELF-DIAGNOSTICS article. Go to next step.
  10. Perform Idle Air Volume Learning. See appropriate SELF-DIAGNOSTICS article. If result is complete, go to next step. If result is incomplete, repair as necessary, then go to step  5.
  11. Start engine and warm to normal operating temperature. Check idle speed. Idle speed should be 600-700 RPM with transmission in Park or Neutral. If idle speed is as specified, go to next step. If idle speed is not as specified, go to step  17.
  12. Check ignition timing at idle with a timing light. Ignition timing should be 12-22 degrees BTDC with transmission in Park or Neutral. If ignition timing is as specified, basic inspection is complete. If ignition timing is not as specified, go to next step.
  13. Check timing chain installation. See appropriate article in ENGINES. If timing chain installation is okay, go to next step. If timing chain installation is not okay, repair as necessary, then go to step  5.
  14. Check the following:
    • Check CMP sensor (PHASE) and circuit. See DTC P0340: CAMSHAFT POSITION SENSOR (PHASE) under DIAGNOSTIC TESTS in appropriate SELF-DIAGNOSTICS article.
    • Check CKP sensor (POS) and circuit. See DTC P0335 OR P1336: CRANKSHAFT POSITION SENSOR (POS)under DIAGNOSTIC TESTS in appropriate SELF-DIAGNOSTICS article.
    If problem is found, repair as necessary, then go to step  5. If problem is not found, go to next step.
  15. Substitute a known-good ECM to check ECM function. Go to step  5.
VALVE CLEARANCE SPECIFICATIONS (1)

Application (2) Cold - In. (mm) Hot - In. (mm)
FX35
Exhaust .011-.015 (.29-.37) .012-.016 (.31-.43)
Intake .010-.013 (.26-.34) .012-.016 (.30-.42)
FX45
Exhaust .011-.015 (.29-.37) .013-.016 (.33-.41)
Intake .010-.013 (.26-.34) .013-.016 (.32-.40)
G35
Exhaust .011-.015 (.29-.37) .012-.016 (.308-.432)
Intake .010-.013 (.26-.34) .012-.016 (.304-.416)
I35
Exhaust .011-.015 (.29-.37) .012-.017 (.308-.432)
Intake .010-.013 (.26-.34) .012-.416 (.304-.416)
M45
Exhaust .011-.015 (.29-.37) .013-.016 (.33-.41)
Intake .010-.013 (.26-.34) .013-.016 (.32-.40)
QX4
Exhaust .011-.015 (.29-.37) .012-.017 (.308-.432)
Intake .010-.013 (.26-34) .012-.016 (.304-.416)
Q45
Exhaust .011-.015 (.29-.37) .013-.016 (.33-.41)
Intake .010-.013 (.26-.34) .013-.016 (.32-.40)
(1) If inspection is performed on a cold engine, ensure clearances are still within specifications when engine is fully warmed up.
(2) About 68°F (20°C).
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