NO.14 FAST IDLE/RUNS ON [SKYACTIV-D 1.5]


id0103q2898100

14

FAST IDLE/RUNS ON

DESCRIPTION
•  Engine speed continues at fast idle after warm-up.
•  Engine runs after ignition is switched off.
POSSIBLE CAUSE
•  Improper engine oil level (close to or exceeds X mark)
•  PCM DTC is stored.
•  Erratic signal to PCM
―  Engine speed signal
•  Fuel injection system malfunction
―  Fuel leakage from fuel system
―  Common rail malfunction
―  Supply pump malfunction
―  Suction control valve malfunction
―  Fuel injector malfunction
―  Fuel pressure relief valve malfunction
•  Mechanical (engine) malfunction
―  Engine oil malfunction (oil working up or down)


Diagnostic Procedure

STEP

INSPECTION

RESULTS

ACTION

1
INSPECT ENGINE OIL LEVEL
•  Inspect the engine oil level.
•  Is the engine oil level closed to or exceeds X mark?
Yes
Replace the engine oil and perform the “ENGINE OIL DATA RESET”.
No
Go to the next step.
2
VERIFY PCM DTC
•  Retrieve PCM DTCs using the M-MDS.
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
No
Go to the next step.
3
VERIFY CURRENT INPUT SIGNAL STATUS
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 following PIDs using the M-MDS:
―  RPM
―  ARPMDES
•  Is the difference between the RPM monitor value and the ARPMDES monitor value within the specified value?
Yes
Inspect the related sensor and circuit.
•  If there is any malfunction:
―  Repair or replace the malfunctioning part according to the inspection results, then go to Step 6.
•  If there is no malfunction:
―  Go to the next step.
No
Go to the next step.
4
INSPECT FOR FUEL LEAKAGE FROM FUEL SYSTEM
•  Visually inspect the following:
―  Fuel leakage from the fuel tank, fuel pump, hose, pipe, fuel injector, supply pump, common rail
―  Cracking and damage in fuel hose and pipe
―  Clamp installation condition for each hose and pipe
―  Fuel pipe securing condition due to deterioration such as rubber of clamp
•  Are all items normal?
Yes
Go to the next step.
No
Repair or replace the malfunctioning part according to the inspection results, then go to Step 6.
5
INSPECT FUEL INJECTION RELATED PARTS
•  Inspect the following parts:
―  Common rail
―  Supply pump
―  Suction control valve
―  Fuel injector
―  Fuel pressure relief valve
•  Are all items normal?
Yes
Inspect for the following engine internal parts:
•  Cylinder
•  Piston ring
•  Intake valve
•  Exhaust valve
•  Such as cylinder head gasket
Repair or replace the malfunctioning part according to the inspection results, then go to the next step.
No
Repair or replace the malfunctioning part according to the inspection results, then go to the next step.
6
Verify the test results.
•  If normal, return to the diagnostic index to service any additional symptoms.
•  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.