P1131Lack of HO2S Switch — Sensor Indicates Lean (Bank 1)
The bank 1 oxygen sensor on Ford permanently indicates a lean mixture.
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Can I keep driving? With caution
You can drive to the shop, but do not postpone the repair. The problem may worsen and damage other components.
Sistema Afectado
Motor · Powertrain
La falla pertenece al grupo motopropulsor (motor y gestión electrónica).
Espacio para vendedores de repuestos
Aún no hay un anunciante en este espacio.
Symptoms You Will Notice
What you may observe when this code appears
- Rough idle
- Hesitation on acceleration
- Variable consumption
Possible Causes
The components or conditions that trigger this code
- 1Vacuum leak
- 2Dirty MAF sensor
- 3Faulty HO2S sensor
- 4Exhaust leak
How to Fix It — Step by Step
Recommended diagnostic and repair procedure
- 1Look for vacuum leaks
- 2Clean the MAF sensor
- 3Replace the HO2S sensor if needed
Note: This information is for general reference. For precise diagnostics and safety repairs, always consult a certified mechanic.
Estimated Cost
Approximate range in USD (varies by region and shop)
Varies by diagnosis
* Diagnosis only: $50–$150
Quick Info
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