Yes, you can typically drive in the near term, but you should address a P0137 code soon. This indicates a problem with the downstream O2 sensor circuit (Bank 1 Sensor 2) and can affect emissions and fuel economy. Plan to diagnose the issue and arrange repairs promptly.
What P0137 Indicates
The code P0137 stands for O2 Sensor Circuit Low Voltage (Bank 1 Sensor 2). This sensor sits downstream of the catalytic converter on the Bank 1 side and is used to monitor catalytic efficiency. A consistently low voltage reading suggests the sensor isn’t reporting properly, or there is a related wiring, connector, or exhaust issue.
Where the sensor sits
Bank 1 Sensor 2 is the post-cat oxygen sensor on the first bank of cylinders. It provides feedback to the engine computer about how well the catalytic convertor is working rather than directly controlling fuel mixture.
What a low voltage implies
A voltage reading below the normal operating range (often under roughly 0.2 volts) can indicate a faulty sensor, damaged wiring, a bad connection, or an exhaust issue that affects the sensor’s signal.
Is it Safe to Drive with P0137?
Most vehicles will still run and drive with a P0137 code, but you may notice worse fuel economy, a slight change in throttle response, or emissions-related concerns. If the check engine light is solid rather than flashing, you’re unlikely to face immediate mechanical danger, but avoid aggressive driving and long trips until the issue is diagnosed. If you experience rough running, misfires, overheating, or the vehicle stalls, stop and seek service promptly.
Common Causes
The following are frequent reasons a P0137 code appears. If one of these is suspected, a professional diagnosis is recommended to confirm before replacing parts.
- Faulty downstream O2 sensor (Bank 1 Sensor 2)
- Exhaust leaks before or near the downstream sensor
- Poor sensor ground or voltage reference issues
- ECU/PCM fault or software needing an update
- Intermittent sensor signal due to aging components
Identifying the exact cause often requires diagnosing the sensor circuit with a scan tool, checking live sensor data, and inspecting wiring and exhaust plumbing.
What to Do Next
Use this sequence to approach the issue methodically and safely.
- Scan for codes and view live data with a reliable OBD-II scanner to confirm P0137 and check related codes (e.g., P0136, P0138, P0420).
- Inspect the downstream O2 sensor and its wiring/connector for signs of damage, corrosion, or loose connections.
- Check for exhaust leaks before or around the sensor, which can affect readings.
- Test or replace the sensor if it’s proven faulty or shows erratic readings.
- If the sensor and wiring appear okay, consider a software/ECU update or professional diagnostic to rule out a PCM issue.
After performing these steps, clear the codes and monitor whether they reappear. If the code returns, pursue the recommended repair path based on the confirmed cause.
Repair Options and Typical Costs
Repair costs vary by vehicle and your location. The following options cover common scenarios you may encounter when addressing P0137.
- Replace Bank 1 Sensor 2 (downstream O2 sensor): parts typically $50–$150; labor $40–$150; total commonly $90–$300.
- Repair or replace damaged wiring or connectors in the O2 sensor circuit: costs depend on the extent of damage; often $50–$200 for parts and labor.
- Address exhaust leaks (before the sensor): gasket or pipe repairs can range from $100–$400 depending on access and parts.
- ECU/software update or reprogramming (if advised by the dealer or shop): usually $50–$150.
- If downstream sensor replacement doesn’t resolve the code, additional diagnostics may be needed to rule out catalytic converter or PCM issues, which can be more costly.
Note: These are ballpark figures and can vary by vehicle make/model and regional labor rates. Always obtain a written estimate before any repair.
Emissions, Inspection, and Driving Tips
A persistent P0137 can cause the vehicle to fail an emissions inspection in some regions, since the downstream sensor helps monitor catalyst efficiency. If you’re approaching an inspection, plan repairs promptly to avoid failure. While driving, avoid unnecessary trips and heavy throttle if you’re waiting for parts or a professional diagnosis.
Summary
A P0137 code indicates a problem with the downstream O2 sensor circuit (Bank 1 Sensor 2). In most cases, you can still drive, but the issue should be diagnosed and repaired to restore proper emissions monitoring and fuel economy. Start with a diagnostic scan, inspect wiring and exhaust integrity, and consider replacing the downstream sensor if it’s faulty. If symptoms worsen or the vehicle behaves unusually, seek professional service promptly.
Bottom line: you can usually continue driving temporarily, but plan to fix P0137 soon to protect emissions, efficiency, and long-term reliability. Schedule a diagnostic with a qualified technician to confirm the exact cause and the best repair path.