P200F: Catalyst System Over Temperature (Bank 2)

What it means

The control module has detected catalyst system overtemperature on bank 2. The code does not establish a particular catalyst design or the cause of the high temperature.

At a glance

• Usually lights the check-engine light
• Affects emissions; the car can fail an emissions test

How it works

The catalytic converter in bank 2's exhaust reduces harmful emissions, and the control module monitors catalyst temperature or related signals, depending on vehicle design. P200F sets when it detects that the bank 2 catalyst system is too hot; the code alone does not identify the cause or the catalyst design.

Common causes

Most likely first.

1. Engine misfire sending unburned fuel into the catalyst
2. Rich air-fuel mixture
3. Faulty oxygen or air-fuel sensor
4. Exhaust leak or fuel control fault

Symptoms

• Check engine light on
• Failed emissions inspection
• Possibly slightly increased fuel consumption
• Sulfur (rotten egg) smell from exhaust under load

How to diagnose it

1. Record freeze-frame data and check for related misfire, fuel-trim, and oxygen or air-fuel sensor codes to see what was happening when bank 2 overheated.
2. Inspect bank 2 exhaust joints and sensor wiring for leaks, damage, or loose connections that could affect mixture control or temperature readings.
3. Check live misfire counts and fuel trims for bank 2, and compare them with the other bank under similar conditions.
4. Test the bank 2 oxygen or air-fuel sensor signals and their circuits against the manufacturer's specification.
5. If mixture and misfire checks are normal, follow the vehicle's procedure to assess catalyst temperature or efficiency before replacing the catalyst.

Common fixes

• Repair an exhaust leak or damaged sensor wiring on bank 2.
• Replace a faulty bank 2 oxygen or air-fuel sensor after confirming its signal or circuit is defective.
• Repair the cause of a rich mixture, such as a fuel-control fault.
• Diagnose and repair any engine misfire before further driving under load.
• Replace the bank 2 catalyst only if testing confirms it is damaged or overheating.

Can I keep driving?

Avoid hard acceleration, towing, and prolonged driving under load until the cause is found, since an active misfire or rich mixture can overheat and damage the bank 2 catalyst. If the engine runs roughly, the warning light flashes, or you smell sulfur strongly, stop driving and arrange prompt inspection.