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2015 TOYOTA HIGHLANDER
2.7L I4•FWD•AUTOMATIC•gas•1AR-FE
2 active safety recalls on this vehicle — view recalls
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Repairs0Labor478Torque4164Fluid10DTC1177Battery1Maintenance0Recalls2
P0174high severityPowertrain

System Too Lean Bank 2

on 2015 Toyota Highlander 2.7L I4 · FWD

What this code means

The long-term fuel trim for Bank 2 has exceeded the positive limit, indicating lean running on Bank 2.

Symptoms

  • Check Engine Light
  • Rough idle
  • Hesitation
  • Possible misfires

Common causes

  • Vacuum leak Bank 2 side
  • Low fuel pressure
  • Faulty MAF sensor
  • Exhaust leak Bank 2
  • Clogged injector Bank 2

Diagnostic steps

  1. Check fuel trim Bank 2
  2. Smoke test Bank 2 intake
  3. Test fuel pressure
  4. Test MAF sensor
  5. Check for exhaust leaks Bank 2

Repair notes

Same diagnostic approach as P0171 but focused on Bank 2.

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🔧 Database maintained under the daily editorial review of Chris Hackleman · Master Technician · 20+ years and Jeff Moore · Master Mechanic · 20+ years. Spot an error? Use the Help link above — a human reads every report.
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