i have a check engine light
looking for oxygen sensor 1 bank1 from from driver side on 2002 Pontiac Aztek
Bank 1, sensor 1, will be the first sensor you get to before the cat. convertor. Start following the exhaust system from the front of the engine towards the back the first oxygen sensor you get to is the one you are looking for. You will need a 7/8" wrench to remove and install the new one. You will also need to have the code reset, this can be done at your local auto parts store free.