Originally Posted by BC_ZX3
Low coolant level, faulty coolant temperature sensor or stuck open thermostat are the likely causes.
The code is telling you that the ECU can't operate the fuel system in a closed loop fashion - where the air fuel ratio is "tweaked" for optimum efficiency using inputs from various engine sensors - because the engine is taking too long or never reaching its normal operating temperature, a prerequisite to entering closed loop functionality. Consequently, it's may be running rich all the time in an attempt to "warm up".
wow this makes sense...my car just threw this same code at the same time as p0420 something about my car running too rich bank 1 or something along those lines...could a bad thermostat or temp. sensor be causing my car too through this other code