NO.9 FAST IDLE/RUNS ON [MZR-CD (RF Turbo)]


9	RUNS IDLE/RUNS ON
DESCRIPTION	• Engine speed continues at fast idle after warm up. • Engine runs after engine key turned off.
POSSIBLE CAUSE	• ECT sensor or related circuit malfunction • Incorrect adjustment accelerator pedal position sensor and/or idle switch • Suction control valve (built-in supply pump) • Fuel injector malfunction • IDM or related circuit 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 [MZR-CD (RF Turbo)].) (See AFTER SERVICE PRECAUTION [MZR-CD (RF Turbo)].)


STEP	INSPECTION	RESULTS	ACTION
1	Connect the WDS or equivalent to the DLC-2. Access ECT PID. Start and warm up the engine to normal operating temperature. Is ECT PID reading between 82-112 °C {180-233 °F}?	Yes	Go to the next step.
1		No	ECT PID is higher than 112 °C{233 °F}: Go to symptom troubleshooting "NO.17 COOLING SYSTEM CONCERNS-OVERHEATING". (See NO.17 COOLING SYSTEM CONCERNS-OVERHEATING [MZR-CD (RF Turbo)].) ECT PID is less than 82 °C{180 °F}: Go to symptom troubleshooting "NO.18 COOLING SYSTEM CONCERNS-RUNS COLD". (See NO.18 COOLING SYSTEM CONCERNS-RUNS COLD [MZR-CD (RF Turbo)].)
2	Perform self-test function using the WDS or equivalent. Turn the engine switch to the ON position. Retrieve any DTC. Is DTC displayed?	Yes	DTC is displayed: Go to the applicable DTC inspection. (See DTC TABLE [MZR-CD (RF Turbo)].) Communication error message is displayed: Inspect for the following: • Open circuit between PCM control relay and PCM terminal 53 or 79 • Open circuit PCM control relay and PCM terminal 69 • PCM control relay stuck open • Open or poor GND circuit (PCM terminal 65, 85, 103 or 104) • Poor connection vehicle body GND
2		No	No DTC is displayed: Go to the next step.
3	Inspect the suction control valve. (See SUCTION CONTROL VALVE INSPECTION [MZR-CD (RF Turbo)].) Is the suction control valve normal?	Yes	Go to the next step.
3		No	Repair the supply pump. (See SUPPLY PUMP INSPECTION [MZR-CD (RF Turbo)].)
4	Inspect the fuel injector. (See FUEL INJECTOR INSPECTION [MZR-CD (RF Turbo)].) Is the fuel injector normal?	Yes	inspect the accelerator pedal position sensor and the idle switch.
4		No	Replace the fuel injector. (See FUEL INJECTOR REMOVAL/INSTALLATION [MZR-CD (RF Turbo)].)
5	Verify test results. • If normal, return to diagnostic index to service any additional symptoms. • If malfunction remains, replace the PCM. (See PCM REMOVAL/INSTALLATION [MZR-CD (RF Turbo)].)