P1191 – Manufacturer Specific Fuel/Air Sensor Fault

Description

A manufacturer-specific fault in the air/fuel metering or sensor system.

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Symptoms

  • Poor acceleration
  • High fuel consumption
  • Car runs lean

Causes

  • Faulty air/fuel sensor
  • Vacuum leak
  • Fuel trim imbalance

Diagnosis

  • Check sensor data
  • Inspect vacuum lines
  • Scan fuel trim values

Repair

  • Replace sensor
  • Fix vacuum leak
  • Correct fuel trim issue