FixVault

Fast Idle/Runs On: Outline

FAST IDLE/RUNS ON (SKYACTIV-G) DESCRIPTION AND POSSIBLE CAUSE

Troubleshooting item 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 detects DTCs
  • Accelerator pedal stuck depressed
  • Erratic signal to PCM
    • APP sensor or related wiring harness malfunction
    • Clutch stroke sensor or related circuit malfunction (MT)
    • Communication error between TCM and PCM (AT)
    • ECT sensor or related wiring harness malfunction
    • A/F sensor or related wiring harness malfunction
    • HO2S or related wiring harness malfunction
  • Improper load signal (A/C) input
    • A/C request signal
  • Improper operation of drive-by-wire control system
  • Throttle body malfunction
  • Fuel injector malfunction
  • Spill valve control solenoid valve malfunction (built-into high pressure fuel pump)
  • Vacuum leakage
  • 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. (Refer to BEFORE SERVICE PRECAUTION [SKYACTIV-G 2.0] in service information.)
        • 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. (Refer to

        QUICK RELEASE CONNECTOR REMOVAL/INSTALLATION [SKYACTIV-G 2.0] in service information.) (Refer to AFTER SERVICE PRECAUTION [SKYACTIV-G 2.0] in service information.)

    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.
System wiring diagram
  • Not applicable