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Home >> Honda >> 2021 >> Insight EX >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Advanced Diagnostics (1 Of 2) >> Advanced Diagnostics >> DTC P0171 >> Possible Cause
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Possible Cause

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
  • Fuel pump failure
  • Fuel injector failure
  • Fuel pressure regulator failure
  • Fuel line failure
  • Fuel supply system failure
  • Mass air flow (MAF) sensor range/performance problem
  • Manifold absolute pressure (MAP) sensor range/performance problem
  • A/F sensor (sensor 1) failure
  • Secondary HO2S (sensor 2) failure
  • Vacuum hose misinstalled
  • Throttle body air leak
  • Intake manifold air leak
  • EVAP canister purge valve failure