P0130 - O2 Sensor Circuit Malfunction (Bank 1 Sensor 1)

An oxygen sensor circuit issue was detected.

Code Overview

An oxygen sensor circuit issue was detected.

Common Causes

• Failing upstream oxygen sensor on bank 1 sensor 1
• Damaged wiring or poor terminal contact in the sensor circuit
• Exhaust leak ahead of the sensor
• Rich or lean running condition affecting the signal

Symptoms

• Check-engine light with unstable fuel trims
• Rough idle or light hesitation
• Reduced fuel economy

Diagnostic Steps

1. Check for fuel-trim, misfire, or exhaust-leak issues first
2. Inspect the bank 1 sensor 1 harness near the exhaust for damage
3. Watch the upstream O2 sensor switch activity on the scan tool
4. Verify power, ground, and signal integrity before replacing the sensor

Repair Difficulty

Moderate

General difficulty estimate for the most common repair path.

Likely Repairs & Cost Guides

Use test results to confirm the fault before pricing the repair.

Related OBD Codes

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Next Steps

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