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No.9 Fast Idle/Runs On: Notes

DESCRIPTION & POSSIBLE CAUSE

9	FAST IDLE/RUNS ON
DESCRIPTION	Engine speed continues at fast idle after warm-up. Engine runs after ignition switch is turned off.
POSSIBLE CAUSE	Cooling system malfunction PCM DTC is stored Accelerator pedal stuck depressed Erratic signal to PCM APP sensor or related circuit malfunction CPP switch or related circuit malfunction (MTX) Neutral switch or related circuit malfunction (MTX) Communication error between TCM and PCM (ATX) A/F sensor or related circuit malfunction HO2S or related circuit malfunction Improper air/fuel mixture ratio control operation 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 (built-into high pressure fuel pump) malfunction Improper operation of cruise control system 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. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injury or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION ). (See AFTER SERVICE PRECAUTION ). 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.

CAUTION:

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

RELATED PIDs DESCRIPTION

Monitor item (Definition)	Unit/Condition	Condition/Specification (Reference)
ECT	°C, °F	Displays the ECT
ECT	V	ECT is 20°C {68°F}: approx. 3.10 V ECT is 40°C {104°F}: approx. 2.16 V ECT is 60°C {140°F}: approx. 1.40 V ECT is 80°C {176°F}: approx. 0.87 V ECT is 100°C {212°F}: approx. 0.54 V
APP1	%	Accelerator pedal released: approx. 16 % Accelerator pedal depressed: approx. 80 %
APP1	V	Accelerator pedal released: approx. 0.8 V Accelerator pedal depressed: approx. 4 V
APP2	%	Accelerator pedal released: approx. 8 % Accelerator pedal depressed: approx. 40 %
APP2	V	Accelerator pedal released: approx. 0.4 V Accelerator pedal depressed: approx. 2 V
CPP (MTX)	OFF/ON	Clutch pedal depressed: On Clutch pedal released: Off
CPP/PNP (MTX)	OFF/ON	Neutral: On Other than neutral: Off
VSS	KPH, MPH	Displays the vehicle speed
RPM	RPM	Displays the engine speed
O2S11	A	Idle (after warm up): approx. -39 μA Deceleration fuel cut (accelerator pedal released from engine speed of 4,000 rpm or more): approx. 3.84 mA
O2S12	V	Idle (after warm up): 0-1.0 V Deceleration fuel cut (accelerator pedal released from engine speed of 4,000 rpm or more): approx. 0 V
SHRTFT1	%	Idle (after warm up): approx. 1.56 % Racing (engine speed is 2,000 rpm ): approx. -3.12 % Racing (engine speed is 4,000 rpm ): approx. -8.59 %
LONGFT1	%	Idle (after warm up): approx. -2.34 % Racing (engine speed is 2,000 rpm ): approx. -0.78 % Racing (engine speed is 4,000 rpm ): approx. -0.78 %
AC_REQ	OFF/ON	A/C switch OFF: Off A/C switch ON: On
TP REL	%	Accelerator pedal released: approx. 12 % Accelerator pedal depressed: approx. 82 %
FUEL_PRES	KPa {MPa}, mBar {Bar}, psi, in H20	Displays the fuel pressure
FUEL_PRES	V	Fuel pressure is 3.0 MPa {31 kgf/cm ² , 435 psi}: approx. 0.92 V Fuel pressure is 4.8 MPa {49 kgf/cm ² , 696 psi}: approx. 1.17V
LOAD	%	Idle (after warm up): approx. 16.07 % Racing (engine speed is 2,000 rpm ): approx. 14.51 % Racing (engine speed is 4,000 rpm ): approx. 21.17 %