Presume you're referring to oxygen sensors. If so, Bank 1 is usually the passenger side exhaust system, each exhaust system has two sensors; one in front of the cat, one after. Sensor 2 is the one after. Straight forward to replace, but you'll require a special 7/8 wrench to access properly (cost is ~$15).
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Presume you're referring to oxygen sensors. If so, Bank 1 is usually the passenger side exhaust system, each exhaust system has two sensors; one in front of the cat, one after. Sensor 2 is the one after. Straight forward to replace, but you'll require a special 7/8 wrench to access properly (cost is ~$15).