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No. 9 - Fast Idle/Runs On: Notes

NO. 9 FAST IDLE/RUNS ON DESCRIPTION AND POSSIBLE CAUSE

9

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
Communication error between TCM and PCM
ECT sensor No. 1 or related circuit malfunction
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.
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. (See BEFORE SERVICE PRECAUTION .)

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. (See QUICK RELEASE CONNECTOR REMOVAL/INSTALLATION .) (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.