Q: How many oxygen sensors are there on a vehicle?

asked by on November 06, 2016

Need to know how many o2 sensors there are total, and if possible the locations of them. Its a 2004 Mazda 6, v6. I think its 2 o2 sensors but im not sure. My car has a manual transmission.

Your vehicle and engine will have four O2 sensors. There is one O2 sensor in each exhaust manifold and one after each catalyst. This is a diagram of your exhaust system to see O2 sensor locations.

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