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No. 9 Fast Idle/Runs On

POSSIBLE CAUSE

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 WDS or equivalent 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 WDS or equivalent 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.
(See DTC TABLE ).
No No DTC is displayed: 
Go to the next step.
3 Measure voltages at PCM terminal 1AP, 1R, 1O (MTX) and 1S.
(See PCM INSPECTION ).
Are voltage normal?		 Yes Go to the next step.
No If PCM terminal 1AU (1) , 1AP (2) , 1AU (3)  voltage is not specified: 
Inspect A/C switch, refrigerant pressure switch and fan switch.
If PCM terminal 1J (1) , 1R (2) , 1J (3)  voltage is not specified: 
Inspect refrigerant pressure switch (middle pressure).
If PCM terminal 1D voltage is not specified: 
Inspect clutch pedal position (CPP) switch.
(See CLUTCH PEDAL POSITION (CPP) SWITCH INSPECTION ).
If PCM terminal 1X voltage is not specified: 
Inspect neutral switch (MTX), transaxle range (TR) switch (ATX).
(See NEUTRAL SWITCH INSPECTION ).
(See TRANSAXLE RANGE (TR) SWITCH INSPECTION ).
(See TRANSAXLE RANGE (TR) SWITCH INSPECTION ).
4 Connect the WDS or equivalent to the DLC-2.
Start the engine and idle it.
Retrieve any DTCs for EHPAS.
Is there any EHPAS DTC displayed?		 Yes DTC is displayed: 
Go to appropriate DTC inspection.
No No DTC is displayed: 
Go to the next step.
5 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
6
  • Verify test results.
    • If normal, return to diagnostic index to service any additional symptoms.

      (See ENGINE SYMPTOM TROUBLESHOOTING ).

    • If malfunction remains, inspect related Service Bulletins and/or On-line Repair 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.

        (See PCM REMOVAL/INSTALLATION ).
(1) California emission regulation applicable model
(2) Except for California emission regulation applicable model with LF engine ATX
(3) Except for California emission regulation applicable model with LF engine MTX and L3 engine
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