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Home >> Mazda >> 2020 >> CX-30 Base, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Symptom Troubleshooting - Engine >> Spark Plug Condition >> Diagnostic Procedure
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Diagnostic Procedure

SPARK PLUG CONDITION (SKYACTIV-G) DIAGNOSTIC PROCEDURE

Step Inspection Results Action
1 VERIFY SPARK PLUG CONDITION
 Yes Specific plug is wet or covered with carbon:
  • Go to the next step.

Specific plug looks grayish white:
  • Go to Step 7.

All plugs are wet or covered with carbon:
  • Go to Step 9.

All plugs look grayish white:
  • Go to Step 15.
No Symptom troubleshooting completed.
2 DETERMINE IF MALFUNCTION CAUSE IS ENGINE OIL LOSS OR OTHER
  • Are the spark plugs wet/covered with carbon from the engine oil?
 Yes Inspect all areas related to oil, working up and down.
  • If there is any malfunction:
    • Repair or replace the malfunctioning location and perform the repair completion verification.
No Go to the next step.
3 INSPECT SPARK PLUG
 Yes Replace the spark plug and perform the repair completion verification.
(See SPARK PLUG REMOVAL/INSTALLATION [SKYACTIV-G (VIN M (US))] .)
(See SPARK PLUG REMOVAL/INSTALLATION [SKYACTIV-G (VIN L (US))] .)
No Go to the next step.
4 INSPECT ENGINE COMPRESSION
 Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
5 INSPECT IGNITION SYSTEM OPERATION
 Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
6 INSPECT FUEL LINE PRESSURE
 Yes Inspect the fuel injector for the following:
No Zero or low:

High:
7 INSPECT SPARK PLUG
  • Inspect the spark plug for the following:
    • Air gap
      • Heat range
  • Is there any malfunction?
 Yes Replace the spark plug and perform the repair completion verification.
(See SPARK PLUG REMOVAL/INSTALLATION [SKYACTIV-G (VIN M (US))] .)
(See SPARK PLUG REMOVAL/INSTALLATION [SKYACTIV-G (VIN L (US))] .)
No Go to the next step.
8 INSPECT FUEL INJECTOR OPERATION
 Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
9 INSPECT AIR CLEANER ELEMENT
 Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
(See AIR CLEANER ELEMENT REMOVAL/INSTALLATION [SKYACTIV-G (VIN M (US))] .)
(See AIR CLEANER ELEMENT REMOVAL/INSTALLATION [SKYACTIV-G (VIN L (US))] .)
10 VERIFY CURRENT INPUT SIGNAL STATUS
 Yes Go to the next step.
No ECT, ECT_VOLT PIDs are not as specified:
ECT2, ECT2_VOLT PIDs are not as specified:
MAF PID is not as specified:
A/F_SEN_CUR PID is not as specified:
HO2S_OUT_VOLT PID is not as specified:
Repair or replace the malfunctioning location and perform the repair completion verification.
11 INSPECT PURGE CONTROL SYSTEM OPERATION
 Yes Repair or replace the malfunctioning location and perform the repair completion verification.
No Go to the next step.
12 INSPECT IGNITION SYSTEM OPERATION
 Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
13 INSPECT ENGINE COMPRESSION
 Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
14 INSPECT FUEL LINE PRESSURE

Specification:
  • 475-555 kPa {4.85-5.65 kgf/cm2 , 68.9-80.4 psi}
 Yes Visually inspect for deformed exhaust system parts.
  • If there is any malfunction:
    • Repair or replace the malfunctioning location and perform the repair completion verification.
No Zero or low:

High:
15 VERIFY CURRENT INPUT SIGNAL STATUS
 Yes Go to the next step.
No ECT, ECT_VOLT PIDs are not as specified:

ECT2, ECT2_VOLT PIDs are not as specified:

MAF PID is not as specified:

A/F_SEN_CUR PID is not as specified:

HO2S_OUT_VOLT PID is not as specified:

Repair or replace the malfunctioning location and perform the repair completion verification.
16 INSPECT INTAKE-AIR SYSTEM FOR AIR SUCTION
 Yes Repair or replace the malfunctioning location and perform the repair completion verification.
No Go to the next step.
17 INSPECT FUEL LINE PRESSURE

Specification:
  • 475-555 kPa {4.85-5.65 kgf/cm2 , 68.9-80.4 psi}
 Yes Inspect the PCM ground condition.
  • If there is any malfunction:
    • Repair or replace the malfunctioning location and perform the repair completion verification.
No Zero or low:

High:

Repair completion verification
1 VERIFY THAT VEHICLE IS REPAIRED
  • Install/connect the part removed/disconnected during the troubleshooting procedure.
  • Has the malfunction symptom been eliminated?
 Yes Complete the symptom troubleshooting. (Explain contents of repair to customer)
No Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error.
(See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(US)] .)
  • If the CAN communication is normal, perform the diagnosis from Step 1.
    • If the malfunction recurs, go to the next step.
Repair completion verification 2 VERIFY IF MALFUNCTION IS CAUSED BY NOT PERFORMING PCM REPROGRAMMING
  • Verify repair information and verify that there is a new calibration in the PCM.
  • Is there a new calibration in the PCM?
 Yes Perform the PCM reprogramming and verify if the malfunction symptom was corrected.
No Replace the PCM.
(See PCM REMOVAL/INSTALLATION [SKYACTIV-G (VIN M (US))] .)
(See PCM REMOVAL/INSTALLATION [SKYACTIV-G (VIN L (US))] .)
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