P1151 – Ford DTC

Ford DTC P1151 – Lack of Upstream Heated Oxygen Sensor Switch – Sensor Indicates Lean – Bank No. 2

DTC P1151 meaning on Ford

  1. DTC: P1151
  2. Definition: Lack of Upstream Heated Oxygen Sensor Switch – Sensor Indicates Lean – Bank No. 2
  3. Meaning: The engine control module (ECM) has detected that the upstream oxygen sensor on Bank 2 is indicating a lean air-fuel mixture for an extended period.

Ford DTC P1151 symptoms

  • Check Engine Light (CEL) illuminated
  • Decreased fuel efficiency
  • Rough idle or engine misfire
  • Reduced engine performance

Ford DTC P1151 causes

  • Vacuum leaks in the intake system
  • Faulty upstream oxygen sensor (Bank 2 Sensor 1)
  • Fuel system issues such as low fuel pressure or clogged fuel injectors
  • Exhaust leaks near the oxygen sensor

Ford DTC P1151 seriousness

  1. Seriousness: While the vehicle may still be operable with this DTC, prolonged driving with a lean air-fuel mixture can lead to engine damage and increased emissions.

How to diagnose DTC P1151 on Ford

  1. Use a scan tool to retrieve and record freeze frame data and DTCs
  2. Inspect for vacuum leaks in the intake system
  3. Check the operation of the upstream oxygen sensor on Bank 2
  4. Test fuel system components for proper operation
  5. Inspect exhaust system for leaks near the oxygen sensor

How to fix DTC P1151 on Ford

  1. Repair any vacuum leaks in the intake system
  2. Replace the upstream oxygen sensor on Bank 2 if faulty
  3. Address any fuel system issues such as low fuel pressure or clogged injectors
  4. Fix any exhaust leaks near the oxygen sensor

How to erase DTC P1151 on Ford

  1. Use a scan tool to clear the DTC and reset the Check Engine Light
  2. Ensure the repair has been completed successfully before clearing the code

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