How many 02 sensors does a 2003 Chevy Impala have?

A 2003 Chevy Impala typically has one O2 sensor for each catalytic converter. Since it has two catalytic converters (one for each bank of cylinders), it usually has two O2 sensors. However, some models might have more depending on the engine configuration and emissions standards. To be absolutely certain, you should check your owner's manual or a repair manual specific to your vehicle's engine.