Outline Of Diagnosis

2014 Subaru Forester 2.5i, Eng CD FB25BA, Standard TransSECTION Outline Of Diagnosis
WARNING: This page is about a different variant/trim than selected.

Detect that Ξ» value remains high.

Judge as NG when lambda value is determined as abnormal in accordance with driving conditions such as intake air amount, sub feedback control, and front oxygen (A/F) sensor Ξ» value and rear oxygen sensor voltage value.

Ξ» value = Actual air fuel ratio/Theoretical air fuel ratio

Ξ» > 1: Lean

Ξ» < 1: Rich

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:

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