Not sure what you're asking. What are you trying to solve? Which engine do you have? There will be two or four. One is ahead of each catalytic converter and one is after each one.
The front and rear sensors work the same way but they perform different functions. They can't be mixed up by switching plugs because the Engine Computer will think the readings are from the wrong side of the engine.
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Saturday, May 4th, 2013 AT 2:18 PM