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Home >> Mazda >> 2021 >> CX-9 Signature >> Repair and Diagnosis >> Engine Performance >> System >> Symptom Troubleshooting - Engine >> 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 [PCM (SKYACTIV-G 2.5T)] .)
  • 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 [SKYACTIV-G 2.5T] .)
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 [SKYACTIV-G 2.5T] .)
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 [SKYACTIV-G 2.5T] .)
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 [SKYACTIV-G 2.5T] .)
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 [SKYACTIV-G 2.5T] .)
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 [SKYACTIV-G 2.5T] .)
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 [SKYACTIV-G 2.5T] .)
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 [SKYACTIV-G 2.5T] .)
  • 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.