Diagnostic Method

2016 Subaru Legacy 2.5iSECTION Diagnostic Method
WARNING: This page is about a different variant/trim than selected.
  • Idle speed diagnosis 

    Judge as NG when the following conditions are established.

JUDGMENT VALUE

Malfunction Criteria Threshold Value
Actual engine speed - Target engine speed < Value of Map 4
ENGINE COOLANT TEMPERATURE SPECIFICATION

Engine coolant temperature -40 °C (-40 °F) -30 °C (-22 °F) -20 °C (-4 °F) -10 °C (14 °F) 0 °C (32 °F) 10 °C (50 °F) 20 °C (68 °F) 30 °C (86 °F) 40 °C (104 °F) 50 °C (122 °F) 60 °C (140 °F)
Threshold Value -235 rpm -235 rpm -235 rpm -235 rpm -235 rpm -285 rpm -300 rpm -300 rpm -260 rpm -260 rpm -260 rpm

Time Needed for Diagnosis:  7000 ms

Malfunction Indicator Light Illumination:  Illuminates when malfunction occurs in 2 continuous driving cycles.

  • Final ignition timing diagnosis 

Judge as NG when the following conditions are established.

JUDGMENT VALUE

Malfunction Criteria Threshold Value
Final CIT - CSERS CIT*
*:
  • CIT = Commanded Ignition Timing
  • CSERS = Cold Start Emission Reduction Strategy
> Value of Map 5
ENGINE COOLANT TEMPERATURE SPECIFICATION

Engine coolant temperature at engine starting -40 °C (-40 °F) -30 °C (-22 °F) -20 °C (-4 °F) -10 °C (14 °F) 0 °C (32 °F) 10 °C (50 °F) 20 °C (68 °F) 30 °C (86 °F) 40 °C (104 °F) 50 °C (122 °F) 60 °C (140 °F)
Threshold Value 7.5 °CA 7.5 °CA 7.5 °CA 7.5 °CA 7.5 °CA 7.5 °CA 7.5 °CA 7.5 °CA 7.5 °CA 7.5 °CA 7.5 °CA

Time Needed for Diagnosis:  7000 ms

Malfunction Indicator Light Illumination:  Illuminates when malfunction occurs in 2 continuous driving cycles.

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.