NO.9 FAST IDLE/RUNS ON[L3]


id0103a4801500

9

FAST IDLE/RUNS ON

DESCRIPTION
•  The engine speed continues at fast idle after warm-up.
•  The engine runs after the ignition switch is turned off.
POSSIBLE CAUSE
•  ECT sensor malfunction
•  Air leakage from intake-air system
•  Throttle body malfunction
•  Accelerator pedal position sensor misadjustment
•  Cruise control system operation improperly
•  Improper load signal input
•  Improper operation of electronic throttle control system

Diagnostic procedure

STEP

INSPECTION

RESULTS

ACTION

1
Connect the M-MDS to the DLC-2.
Access ECT PID.
Start and warm up engine to normal operating temperature.
Is ECT PID between 82—112°C {180—234°F}?
Yes
Go to the next step.
No
ECT PID is higher than 112°C {234°F}:
Go to symptom troubleshooting "No.17 Cooling system concerns-Overheating".
ECT PID is less than 82°C {180°F}:
Go to symptom troubleshooting "No.18 Cooling system concerns-Runs cold".
2
Connect the M-MDS to the DLC-2.
Turn the ignition switch to the ON position (Engine off).
Retrieve any DTCs.
Are there any DTCs displayed?
Yes
DTC is displayed:
Go to the appropriate DTC inspection.
No
No DTC is displayed:
Go to the next step.
3
Connect the M-MDS to DLC-2
Access ACSW, COLP, CPP/PNP, TR and PSP PIDs.
Monitor each PID.
Are PIDs value okay?
Yes
Go to the next step.
No
ACSW PID is not specified: Inspect A/C switch, refrigerant pressure switch and fan switch.
COLP PID is not specified: Inspect refrigerant
pressure switch (middle pressure).
TR PID: TR switch
PSP PID: Inspect P/S pressure switch.
4
Is there air leakage felt or heard at intake-air system components while racing engine to higher speed?
Yes
Repair or replace parts if necessary.
No
Inspect the following:
•  Electronic throttle control system operation
•  Accelerator pedal position sensor
5
•  Verify test results.
―  If normal, return to diagnostic index to service any additional symptoms.
―  If malfunction remains, inspect related Service Information and perform repair or diagnosis.
•  If vehicle is repaired, troubleshooting completed.
•  If vehicle is not repaired or additional diagnostic information is not available, replace the PCM.