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Home >> Mazda >> 2016 >> 6 Touring, Automatic Trans >> Repair and Diagnosis >> Engine Performance >> System >> Symptom Troubleshooting - Engine Control System >> No. 21 Engine Noise >> Diagnostic Procedure
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Diagnostic Procedure

STEP INSPECTION RESULTS ACTION
1 VERIFY IF THERE IS SQUEAL, CLICK, OR CHIRP SOUND 
  • Is squeal, click or chirp sound present?
Yes Inspect the following:
  • Engine oil level
  • Solenoid valves installation
  • Drive belt tension
  • Generator installation
  • Auto tensioner bearing damaged
  • Splash shield or under cover loose
    • If there is any malfunction:
      • Repair or replace the malfunctioning part according to the inspection results.
    • If there is no malfunction:
      • Go to the next step.
No Go to the next step.
2 VERIFY IF THERE IS RUMBLE OR GRIND SOUND 
  • Is rumble or grinding sound present?
Yes Inspect the following:
  • Drive belt tension
  • Loose parts in engine compartment
    • If there is any malfunction:
      • Repair or replace the malfunctioning part according to the inspection results.
    • If there is no malfunction:
      • Go to the next step.
No Go to the next step.
3 VERIFY IF THERE IS HISS SOUND 
  • Is hiss sound present?
Yes Inspect the following:
  • Vacuum leakage
  • Spark plug loose
  • Intake-air system leakage
    • If there is any malfunction:
      • Repair or replace the malfunctioning part according to the inspection results.
    • If there is no malfunction:
      • Go to the next step.
No Go to the next step.
4 VERIFY IF THERE IS RATTLE SOUND 
  • Is rattle sound present?
Yes Inspect the location of rattle for loose parts.
  • If there is any malfunction:
    • Repair or replace the malfunctioning part according to the inspection results.
  • If there is no malfunction:
    • Go to the next step.
No Go to the next step.
5 VERIFY IF THERE IS RAP OR ROAR SOUND 
  • Is rap or roar sound present?
Yes Inspect the following:
  • Dynamic damper installation
  • Exhaust system installation
  • Intake-air system installation
    • If there is any malfunction:
      • Repair or replace the malfunctioning part according to the inspection results.
    • If there is no malfunction:
      • Go to the next step.
No Go to the next step.
6 VERIFY IF THERE IS KNOCK SOUND 
  • Is knocking noise present?
Yes Perform the symptom troubleshooting "NO. 13 KNOCKING/PINGING-ACCELERATION/CRUISE".
(See NO. 13 KNOCKING/PINGING-ACCELERATION/CRUISE [SKYACTIV-G 2.5] .)
No Inspect the following:
  • Electric variable valve timing actuator
  • Hydraulic variable valve timing actuator
  • Timing chain
  • Hydraulic lash adjuster (HLA) noise
  • Engine compression
    • If there is any malfunction:
      • Repair or replace the malfunctioning part according to the inspection results.
    • If there is no malfunction:
      • Go to the next step.
7 Verify the test results.
  • If normal, return to the diagnostic index to service any additional symptoms.

    (See SYMPTOM DIAGNOSTIC INDEX [SKYACTIV-G 2.5] .)

  • If the malfunction remains, inspect the related Service Bulletins and/or On-line Repair Information and perform repair or diagnosis.
    • If the vehicle is repaired, troubleshooting is completed.
    • If the vehicle is not repaired or additional diagnostic information is not available, reprogram the PCM if a later calibration is available. Retest.