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Troubleshooting Diagnostic Procedure

WARNING: This page is about a different car, the 2016 Mazda CX-5. However, it is still accessible from the selected car via links, so may be relevant.

Intention of troubleshooting procedure 

STEP INSPECTION RESULTS ACTION
1 PURPOSE: DETERMINE INTEGRITY OF SPARK PLUG 
Yes Replace the spark plug, then go to Step 10.
(See SPARK PLUG REMOVAL/INSTALLATION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
No Go to the next step.
2 PURPOSE: DETERMINE INTEGRITY OF IGNITION COIL 
Yes Replace the ignition coil/ion sensor, then go to Step 10.
(See IGNITION COIL/ION SENSOR REMOVAL/INSTALLATION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
No Go to the next step.
3 PURPOSE: DETERMINE INTEGRITY OF FUEL INJECTOR 
Yes Replace the fuel injector, then go to Step 10.
(See FUEL INJECTOR REMOVAL/INSTALLATION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
No Go to the next step.
4 PURPOSE: VERIFY IF MALFUNCTION RELATED TO INTAKE-AIR SYSTEM IS CAUSE OF MISFIRE 
  • Visually inspect for loose, cracked or damaged hoses on intake air system.
  • Is there any malfunction?
Yes Repair or replace the malfunctioning part according to the inspection results, then go to Step 10.
 
No Go to the next step.
5 PURPOSE: VERIFY IF POOR DRIVE BELT ASSEMBLY IS CAUSE OF MISFIRE 
Yes Assemble drive belt correctly, then go to Step 10.
(See DRIVE BELT REMOVAL/INSTALLATION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
No Go to the next step.
6 PURPOSE: VERIFY IF FOREIGN MATTER ON DRIVE BELT IS CAUSE OF MISFIRE 
  • Verify if oil is on the drive belt.
  • Is there foreign matter on the drive belt?
Yes Remove the foreign matter on the drive belt, then go to Step 10.
No Go to the next step.
7 PURPOSE: DETERMINE INTEGRITY OF DRIVE BELT AUTO TENSIONER 
Yes Replace the drive belt auto tensioner, then go to Step 10.
(See DRIVE BELT AUTO TENSIONER REMOVAL/INSTALLATION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
No Go to the next step.
8 PURPOSE: VERIFY IF MALFUNCTION RELATED TO ENGINE COMPRESSION IS CAUSE OF MISFIRE 
  • Inspect the engine compression.

    (See COMPRESSION INSPECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)

  • Are compression pressures within specification?

    Specification: 

  • Compression [SKYACTIV-G 2.0]
    • Standard: 885 kPa {9.02 kgf/cm 2  , 128 psi} (300 rpm) 
    • Minimum: 708 kPa {7.22 kgf/cm 2  , 103 psi} (300 rpm) 
    • Maximum difference between cylinders: 150 kPa {1.53 kgf/cm 2  , 21.8 psi} (300 rpm) 
  • Compression [SKYACTIV-G 2.5]
    • Standard: 954 kPa {9.73 kgf/cm 2  , 138 psi} (300 rpm) 
    • Minimum: 763 kPa {7.78 kgf/cm 2  , 111 psi} (300 rpm) 
    • Maximum difference between cylinders: 161 kPa {1.64 kgf/cm 2  , 23.4 psi} (300 rpm) 
NOTE:
  • Because the SKYACTIV-G 2.0 and SKYACTIV-G 2.5 retards the intake valve closing timing, compression pressure is low.
Yes Go to the next step.
No Replace or overhaul the engine, then go to Step 10.
9 PURPOSE: VERIFY IF MALFUNCTION RELATED TO SEALING OF ENGINE UNIT (COMBUSTION CHAMBER AND ENGINE COOLANT PASSAGE) IS CAUSE OF MISFIRE 
Yes Engine coolant leakage from the engine (between the combustion chamber and the engine coolant passage) may have occurred.
  • Verify the conditions of the gasket and the cylinder head.
    • If there is any malfunction:
      • Repair or replace the malfunctioning part according to the inspection results, then go to the next step.
No Go to the next step.
10 PURPOSE: VERIFICATION OF VEHICLE REPAIR COMPLETION 
Yes Repeat the inspection from Step 1.

Go to the next step.
No Go to the next step.
11 PURPOSE: VERIFY IF THERE IS ANY OTHER MALFUNCTION 
  • Is any other DTC or pending code stored?
Yes Go to the applicable DTC inspection.
(See DTC TABLE [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
No DTC troubleshooting completed.