P1157 – Ford DTC

Ford DTC P1157 – Lack of Downstream Heated Oxygen Sensor Switch – Sensor Indicates Lean – Bank No. 2

DTC P1157 meaning on Ford

1. DTC: P1157
2. Definition: Lack of Downstream Heated Oxygen Sensor Switch – Sensor Indicates Lean – Bank No. 2
3. Meaning: This diagnostic trouble code (DTC) indicates that the downstream heated oxygen sensor in bank 2 is detecting a lean air-fuel mixture condition.

Ford DTC P1157 symptoms

• Check Engine Light (CEL) illuminated
• Possible decrease in fuel efficiency
• Engine may run rough or hesitate

Ford DTC P1157 causes

• Faulty downstream heated oxygen sensor
• Vacuum leaks in the intake system
• Fuel delivery issues
• Exhaust leaks

Ford DTC P1157 seriousness

1. Severity: Moderate
2. Driving with this issue may lead to decreased fuel efficiency and potential engine performance problems.

How to diagnose DTC P1157 on Ford

1. Use an OBD-II scanner to retrieve the DTC codes
2. Inspect the downstream heated oxygen sensor in bank 2 for any damage or contamination
3. Check for vacuum leaks in the intake system
4. Inspect the exhaust system for leaks

How to fix DTC P1157 on Ford

1. Replace the downstream heated oxygen sensor in bank 2 if faulty
2. Repair any vacuum leaks in the intake system
3. Address any fuel delivery issues
4. Fix any exhaust leaks

How to erase DTC P1157 on Ford

1. After fixing the underlying issue, use an OBD-II scanner to clear the DTC codes
2. Ensure the repair has resolved the problem before clearing the codes

Recommended tools for Ford diagnostics

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