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FAST IDLE/RUNS ON [SKYACTIV-G (E)]

FAST IDLE/RUNS ON [SKYACTIV-G (E)]

 id0103s48896s7

Troubleshooting item

Fast idle/runs on
Description
•  Engine speed continues at fast idle after warm-up.
•  Engine runs after ignition is switched off.
Possible cause
•  Cooling system malfunction
•  PCM DTC is stored
•  Accelerator pedal stuck depressed
•  Erratic signal to PCM
―  APP sensor or related circuit malfunction
―  Clutch stroke sensor or related circuit malfunction (MTX)
―  Communication error between TCM and PCM (ATX)
―  ECT sensor No.1 or related circuit malfunction
―  ECT sensor No.2 or related circuit malfunction
―  A/F sensor or related circuit malfunction
―  HO2S or related circuit malfunction
•  Improper load signal input
―  Improper A/C request signal
•  Improper operation of drive-by-wire control system
•  Throttle body malfunction
•  Fuel injector malfunction
•  Spill valve control solenoid valve malfunction (built-into high pressure fuel pump)
•  Air leakage from intake-air system
•  Injector driver (built-into PCM) malfunction
Warning
•  The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before performing the fuel system services:
―  Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel.
―  Highly pressurized fuel may spray out if the fuel line is cut. Due to the following dangers occurring with a fuel spray, always complete the “Fuel Line Safety Procedure” to prevent the fuel from spraying.
•  Fuel may cause irritation if it comes in contact with skin and eyes.
•  If fuel ignites and causes a fire, it may lead to serious injury or death, and damage to property and facilities.
―  Fuel is highly flammable and dangerous. Fuel line spills and leakage can cause serious injury or death, and damage to equipment. Always refer to the “Quick Release Connector Removal/Installation (fuel system)” before performing the fuel hose installation, and execute the “Fuel Leakage Inspection” after installation.
Caution
•  Disconnecting/connecting the quick release connector without cleaning it may possibly cause damage to the fuel pipe and quick release connector. Always clean the quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.
System wiring diagram
•  Not applicable
Connector diagram
•  Not applicable

Caution
•  Verify the malfunction symptom according to not only the PID value but also the symptom troubleshooting.

Related PIDs

PIDs

Reference
A/C_REQ
(See PID/DATA MONITOR TABLE [PCM (SKYACTIV-G (E))].)
APP1
APP2
CLTCH_PEDAL_POS
ECT
ECT_VOLT
ECT2
ECT2_VOLT
FUEL_PRES
LOAD_CALC
LONG_FUEL_TRIM
A/F_SEN_CUR
HO2S_OUT_VOLT
ENG_RPM
SHRT_FUEL_TRIM
TP_RELAT
VSS

Diagnostic Procedure

Step

Inspection

Results

Action
1
INSPECT COOLING SYSTEM FOR MALFUNCTION
•  Access the ECT PID using the M-MDS.
•  Start the engine and warm it up completely.
•  Is the ECT PID value between 82—112 °C {180—234 °F}?
Yes
Go to the next step.
No
ECT PID value is higher than 112 °C {234 °F}:
•  Perform the symptom troubleshooting "COOLING SYSTEM CONCERNS-OVERHEATING".
ECT PID value is less than 82 °C {180 °F}:
•  Perform the symptom troubleshooting "COOLING SYSTEM CONCERNS-RUNS COLD".
2
VERIFY PCM DTC
•  Perform the DTC inspection for the PCM.
•  Are any DTCs displayed?
Yes
Repair the malfunctioning location according to the applicable DTC troubleshooting.
(See DTC TABLE [PCM (SKYACTIV-G (E))].)
No
Go to the next step.
3
VERIFY CURRENT INPUT SIGNAL STATUS
Warning
•  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:
―  APP1
―  APP2
―  CLTCH_PEDAL_POS (MTX)
―  ECT
―  ECT_VOLT
―  ECT2
―  ECT2_VOLT
―  A/F_SEN_CUR
―  HO2S_OUT_VOLT
―  SHRT_FUEL_TRIM
―  LONG_FUEL_TRIM
•  Do the PIDs indicate the correct values under the malfunction condition?
Yes
Go to the next step.
No
APP1, APP2 PIDs are not as specified:
•  Inspect the APP sensor No.1 and No.2.
CLTCH_PEDAL_POS PID is not as specified: (MTX)
•  Inspect the clutch stroke sensor.
ECT, ECT_VOLT, ECT2, ECT2_VOLT PIDs are not as specified:
•  Inspect the ECT sensor No.1 and No.2.
A/F_SEN_CUR, SHRT_FUEL_TRIM, LONG_FUEL_TRIM PIDs are not as specified:
•  Inspect the A/F sensor.
HO2S_OUT_VOLT PID is not as specified:
•  Inspect the HO2S.
Repair or replace the malfunctioning location.
•  If the malfunction remains:
―  Inspect communication error between TCM and PCM. (ATX)
•  Repair or replace the malfunctioning location and perform the repair completion verification.
―  Perform the “Action for Non-repeatable Malfunction” procedure.
4
DETERMINE IF MALFUNCTION CAUSE IS A/C REQUEST SIGNAL OR OTHER
•  Access the A/C_REQ PID using the M-MDS.
•  Monitor the A/C_REQ PID while turning on and off the air conditioner using the switch on the control panel.
•  Does the A/C_REQ PID value change from on to off according to switch control panel?
Yes
Go to the next step.
No
If the A/C_REQ PID is always ON:
•  Perform the symptom troubleshooting “A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY”.
If the A/C_REQ PID is always OFF:
•  Perform the symptom troubleshooting “A/C DOES NOT WORK SUFFICIENTLY”.
5
DETERMINE IF MALFUNCTION CAUSE IS DRIVE-BY-WIRE CONTROL SYSTEM OR OTHER
•  Will the engine run smoothly at part throttle?
Yes
Go to Step 7.
No
Go to the next step.
6
INSPECT DRIVE-BY-WIRE CONTROL SYSTEM OPERATION
•  Perform the Electronic Control Throttle Operation Inspection.
•  Does the drive-by-wire control system work properly?
Yes
Visually inspect the throttle body (damage/scratching).
•  If there is any malfunction:
―  Repair or replace the malfunctioning location and perform the repair completion verification.
•  If there is no malfunction:
―  Go to the next step.
No
Repair or replace the malfunctioning location and perform the repair completion verification.
7
INSPECT FUEL INJECTOR OPERATION
•  Perform the Fuel Injector Operation Inspection.
•  Do the fuel injectors operate properly?
Yes
Go to the next step.
No
Repair or replace the malfunctioning location and perform the repair completion verification.
8
INSPECT HIGH PRESSURE FUEL PUMP
•  Inspect the high pressure fuel pump.
•  Is there any malfunction?
Yes
Replace the high pressure fuel pump and perform the repair completion verification.
(See HIGH PRESSURE FUEL PUMP REMOVAL/INSTALLATION [SKYACTIV-G (WITH CYLINDER DEACTIVATION (E))].)
(See HIGH PRESSURE FUEL PUMP REMOVAL/INSTALLATION [SKYACTIV-G (WITHOUT CYLINDER DEACTIVATION (E))].)
No
Go to the next step.
9
INSPECT INTAKE-AIR SYSTEM FOR AIR LEAKAGE
•  Inspect for leakage in intake-air system.
•  Is there any leakage?
Yes
Repair or replace the malfunctioning location and perform the repair completion verification.
No
Injector driver malfunction.
•  Replace the PCM.
If the problem remains, overhaul the engine and perform the repair completion verification.
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 [(E)].)
•  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.
•  If the malfunction recurs, replace the PCM.
No
Replace the PCM.
(See PCM REMOVAL/INSTALLATION [SKYACTIV-G (WITH CYLINDER DEACTIVATION (E))].)
(See PCM REMOVAL/INSTALLATION [SKYACTIV-G (WITHOUT CYLINDER DEACTIVATION (E))].)