Bank 1 is the rear O2 sensor, but experience says to change both. The front one is right behind the engine in the middle of the engine compartment. The rear O2 sensor is on the top of the exhaust pipe, just behind the catalytic converter. But the same code that shows it is the O2 sensor (which is P0420), is the same code for the catalytic converter, or a vacuum leak. Make sure if you do change the catalytic converter, ensure that the new one is OBD-2 compliant. And the vacuum leak could possibly come from the manifold gasket. Let me know what the problem was!
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Bank 1 is the rear O2 sensor, but experience says to change both. The front one is right behind the engine in the middle of the engine compartment. The rear O2 sensor is on the top of the exhaust pipe, just behind the catalytic converter. But the same code that shows it is the O2 sensor (which is P0420), is the same code for the catalytic converter, or a vacuum leak. Make sure if you do change the catalytic converter, ensure that the new one is OBD-2 compliant. And the vacuum leak could possibly come from the manifold gasket. Let me know what the problem was!
You have a bad o2 sensor what bank 1 or 2 which sensor 1 or 2
My 2003 chevy impala it will turn on in runs about an hour n it will start to pull n tries to turn off but i put it on neutro n it will stay on