P1131 – Ford DTC

Ford DTC P1131 – Lack of Upstream Heated Oxygen Sensor Switch – Sensor Indicates Lean – Bank No. 1

DTC P1131 meaning on Ford

1. DTC: P1131
2. Definition: Lack of Upstream Heated Oxygen Sensor Switch – Sensor Indicates Lean – Bank No. 1
3. Meaning: This diagnostic trouble code (DTC) indicates that the upstream oxygen sensor in bank 1 is detecting a lean air-fuel mixture.

Ford DTC P1131 symptoms

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

Ford DTC P1131 causes

• Vacuum leaks
• Faulty oxygen sensor
• Fuel system issues
• Exhaust leaks
• Engine misfire

Ford DTC P1131 seriousness

1. Severity: Moderate
2. Driving with this DTC may lead to decreased fuel efficiency and potential engine damage if left unresolved.

How to diagnose DTC P1131 on Ford

1. Use an OBD-II scanner to retrieve the DTC
2. Inspect for vacuum leaks
3. Check the oxygen sensor for proper operation
4. Examine the fuel system for issues
5. Inspect the exhaust system for leaks

How to fix DTC P1131 on Ford

1. Repair any vacuum leaks
2. Replace the upstream oxygen sensor if faulty
3. Address any fuel system problems
4. Fix exhaust leaks
5. Repair engine misfires

How to erase DTC P1131 on Ford

1. Use an OBD-II scanner to clear the DTC
2. If the issue is fixed, the Check Engine Light should turn off

Recommended tools for Ford diagnostics

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