P2099 2007 Ford Fusion Code - Post Catalyst Fuel Trim System Too Rich Bank 2

P2099 indicates that the post-catalyst fuel trim system for Bank 2 is running too rich, meaning there is too much fuel and not enough air in the exhaust stream after combustion.

Common symptoms include decreased fuel efficiency, rough idling, black smoke from the exhaust, a strong fuel smell, and potentially an illuminated check engine light.

Possible causes include a faulty oxygen sensor, a leaking fuel injector, a malfunctioning mass airflow (MAF) sensor, a damaged catalytic converter, or exhaust system leaks.

While the car may still be drivable, prolonged operation with this code can damage the catalytic converter and reduce fuel efficiency. It’s best to address the issue promptly.

Start by inspecting the oxygen sensors and wiring, checking for exhaust leaks, and using a scan tool to monitor live data for fuel trims and oxygen sensor readings.

While unlikely, a heavily clogged air filter can restrict airflow and contribute to a rich condition, so it’s worth inspecting and replacing if dirty.

Common repairs include replacing faulty oxygen sensors, fixing exhaust leaks, cleaning or replacing the MAF sensor, replacing leaking fuel injectors, or repairing the catalytic converter if damaged.

Yes, a failing catalytic converter can affect post-catalyst oxygen sensor readings and potentially cause this code.

Repair costs vary depending on the cause. Oxygen sensor replacement typically costs $150–$300, while catalytic converter repairs can exceed $1,000.

You can clear the code with an OBDII scanner, but it will likely reappear if the underlying problem isn’t resolved. Repeated issues can lead to further engine or emissions system damage.