P2273 2014 GMC Sierra Code - HO2S Signal Stuck Rich Bank 2 Sensor 2

P2273 indicates that the downstream oxygen sensor (Bank 2 Sensor 2) has detected a consistently rich air-fuel mixture, meaning there’s too much fuel compared to air.

Common symptoms include poor fuel economy, black smoke from the exhaust, a strong fuel smell, rough idling, and the check engine light being illuminated.

Potential causes include a faulty downstream oxygen sensor (Bank 2 Sensor 2), a leaking fuel injector, a malfunctioning catalytic converter, an exhaust leak, or issues with the engine control module (ECM).

Diagnosis typically involves using an OBDII scanner to confirm the code, inspecting the oxygen sensor and wiring for damage, checking for exhaust leaks, and testing the fuel injectors for proper function.

Yes, a failing catalytic converter can disrupt the exhaust gases and cause the downstream oxygen sensor to detect a rich condition.

Repairs may include replacing the downstream oxygen sensor (Bank 2 Sensor 2), fixing exhaust leaks, repairing or replacing fuel injectors, or replacing the catalytic converter if it’s faulty.

While the vehicle may still be drivable, ignoring the code can lead to increased fuel consumption, damage to the catalytic converter, and further engine issues over time.

The repair cost varies depending on the issue. Replacing an oxygen sensor typically costs $100-$300, while catalytic converter replacement can range from $1,000 to $2,500.

While a dirty air filter can affect air-fuel ratios, it’s unlikely to cause this specific code. The issue is more likely related to the oxygen sensor or exhaust system.

Regular maintenance such as inspecting the exhaust system, monitoring oxygen sensor performance, and ensuring proper fuel system operation can help prevent this code.