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Home >> Mazda >> 2018 >> CX-9 Signature >> Repair and Diagnosis >> Engine Performance >> System >> Symptom Troubleshooting - Engine Control >> NO. 13 Knocking/Pinging-acceleration/Cruise >> Diagnostic Procedure
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Diagnostic Procedure

NO. 13 KNOCKING/PINGING-ACCELERATION/CRUISE (SKYACTIV-G 2.5T) DIAGNOSTIC PROCEDURE

STEP INSPECTION RESULTS ACTION
1 VERIFY PCM DTC Yes Go to the applicable DTC inspection. (See DTC TABLE [PCM (SKYACTIV-G 2.5T)] .)
No Go to the next step.
2 REPLACE FUEL
  • Drain the remaining fuel in the fuel tank and add the specified fuel.
  • Leave idling for approx. 15 min to refill the hose with fuel.
  • Does the symptom disappear?
Yes Symptom troubleshooting completed.
(If customer has used fuel additive, give them advice not to use it)
No Go to the next step.
3 VERIFY IF MALFUNCTION CAUSE IS OVERHEATING
CAUTION:
  • While performing this step, always operate the vehicle in a safe and lawful manner.
    • When the M-MDS is used to observe monitor system status while driving, be sure to have another technician with you, or record the data in the M-MDS using the PID/DATA MONITOR AND RECORD capturing function and inspect later.
  • Access the ECT PID using the M-MDS. (See On-Board Diagnostic Test .)
  • Is the ECT PID value less than 116 °C {241 °F} during driving?
Yes Go to the next step.
No The cause of this concern could be from the cooling system overheating.
4 VERIFY SPARK PLUG CONDITION Yes Replace the spark plug. (See Spark Plug Removal/Installation .)
No Go to the next step.
5 INSPECT INTAKE AIR SYSTEM FOR AIR SUCTION Yes Repair or replace the malfunctioning part according to the inspection results.
No Go to the next step.
6 INSPECT MAP SENSOR Yes Go to the next step.
No Replace the MAP sensor.
(See Manifold Absolute Pressure (MAP) Sensor/Intake Air Temperature (IAT) Sensor NO. 2 Removal/Installation .)
7 INSPECT BOOST PRESSURE SENSOR/BOOST AIR TEMPERATURE SENSOR Yes Replace the boost pressure sensor/boost air temperature sensor.
(See Boost Pressure Sensor/Boost Air Temperature Sensor Removal/Installation .)
No Go to the next step.
8 INSPECT MAF SENSOR Yes Replace the MAF sensor/IAT sensor No. 1.
(See Mass Air Flow (MAF) Sensor/Intake Air Temperature (IAT) Sensor NO. 1 Removal/Installation .)
No Go to the next step.
9 INSPECT IAT SENSOR NO. 2 Yes Replace the MAP sensor/IAT sensor No. 2.
(See Manifold Absolute Pressure (MAP) Sensor/Intake Air Temperature (IAT) Sensor NO. 2 Removal/Installation .)
No Go to the next step.
10 INSPECT ECT SENSOR NO. 1 Yes Replace the ECT sensor No. 1.
(See Engine Coolant Temperature (ECT) Sensor Removal/Installation .)
No Go to the next step.
11 INSPECT KS Yes Replace the KS, then go to the next step.
(See Knock Sensor (KS) Removal/Installation .)
No Remove the accumulated matter in the cylinder head using the following procedure:
  • Carbon remover
  • Overhauling

Go to the next step.
12 Verify the test results.
  • If normal, return to the diagnostic index to service any additional symptoms. (See Symptom Diagnostic Index .)
  • If a malfunction remains, inspect the related Service Information and perform the repair or diagnosis.
    • If the vehicle is repaired, troubleshooting is completed.
      • If the vehicle is not repaired or additional diagnostic information is not available, replace the PCM. (See PCM Removal/Installation .)