The automobile dictionary meaning of the car engine P2199 Code helps also for solving the car engine. You need to know the process of solving the car engine and you do not know need to know the process of solving the car engine if you engage an automobile engineer. The catalytic converter contains an oxygen sensor in front and behind of the catalytic converter. When the car is warm and running in closed loop mode for long time, the upstream oxygen sensor waveform reading should vary. The P2199 engine code seems a kind of powertrain problem and it is also found in Mercury Zephyr.