What does code P1131 mean on Ford vehicles?
The upstream oxygen sensor indicates a constant lean condition on bank 1.
OBD-II Code Ford
P1131 — Ford — Upstream O2 Sensor Indicates Lean Bank 1
The upstream oxygen sensor indicates a constant lean condition on bank 1.
Common symptoms
- Loss of power
- detonation or pinging
Possible causes
- Vacuum leak
- faulty O2 sensor
Initial recommendation
Check for intake vacuum leaks and verify upstream O2 sensor.
Safety notice
This information is for guidance only. Brand-specific codes may vary by model, year, engine, transmission and vehicle configuration. It does not replace a physical inspection or diagnosis by a qualified mechanic. If the vehicle is unsafe to operate, avoid driving it and seek professional inspection.
Analyze this code with MecaOBD
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