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Fuel Injector Operation Inspection

If simulation function of M-MDS is used: 

STEP INSPECTION ACTION
1 Start the engine and warm it up completely.
Access the INJ_1, INJ_2, INJ_3 and INJ_4 PIDs using the M-MDS.
Refer too ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-G 2.5T)] .)
Turn each fuel injector from on to off using the PIDs for each cylinder.
Does the engine speed drop?
Yes Fuel injectors work properly.
No Engine speed does not drop an any cylinder:
  • Go to the next step.

Engine speed drops on some cylinders:
  • Go to Step 4.
2 Perform the Main Relay Operation Inspection.
Refer too MAIN RELAY OPERATION INSPECTION .)
Does the main relay work properly?
Yes Go to the next step.
No Repair or replace the malfunctioning part according to the inspection results.
3 Inspect the fuel injector of the suspected cylinder.
Refer too FUEL INJECTOR INSPECTION [SKYACTIV-G 2.5T] .)
Is there any malfunction?
Yes Replace the fuel injector.
Refer too FUEL INJECTOR REMOVAL/INSTALLATION [SKYACTIV-G 2.5T] .)
No Inspect the fuel injector power and/or ground systems related wiring harness and connectors for the suspected cylinder.
4 Perform the KOER self test using the M-MDS.
Refer too KOEO/KOER SELF TEST [PCM (SKYACTIV-G 2.5T)] .)
Are the DTCs P0201:00, P0202:00, P0203:00 and/or P0204:00 present?
Yes Go to the appropriate DTC inspection.
Refer too DTC P0201:00 [PCM (SKYACTIV-G 2.5T)] .)
Refer too DTC P0202:00 [PCM (SKYACTIV-G 2.5T)] .)
Refer too DTC P0203:00 [PCM (SKYACTIV-G 2.5T)] .)
Refer too DTC P0204:00 [PCM (SKYACTIV-G 2.5T)] .)
No Go to the next step.
5 Inspect the fuel injector of the suspected cylinder.
Refer too FUEL INJECTOR INSPECTION [SKYACTIV-G 2.5T] .)
Is there any malfunction?
Yes Replace the fuel injector.
Refer too FUEL INJECTOR REMOVAL/INSTALLATION [SKYACTIV-G 2.5T] .)
No Inspect the following for the suspected cylinder:
  • PCM terminals (pulled-out pins, corrosion)
  • Fuel injector terminals (pulled-out pins, corrosion)
  • If all items normal:
  • If not:
    • Repair or replace the malfunctioning part according to the inspection results.

If simulation function of M-MDS is not used: 

STEP INSPECTION ACTION
1 Inspect the fuel injector of the suspected cylinder.
Refer too FUEL INJECTOR INSPECTION [SKYACTIV-G 2.5T] .)
Is there any malfunction?
Yes Replace the fuel injector.
Refer too FUEL INJECTOR REMOVAL/INSTALLATION [SKYACTIV-G 2.5T] .)
No Go to the next step.
2 Inspect the following for the suspected cylinder:
  • Fuel injector power and/or ground system related wiring harnesses and connectors
  • PCM terminals (pulled-out pins, corrosion)
  • Fuel injector terminals (pulled-out pins, corrosion)

Is there any malfunction?
Yes Repair or replace the malfunctioning part according to the inspection results.
No Replace the PCM.
Refer too PCM REMOVAL/INSTALLATION [SKYACTIV-G 2.5T] .)