how many 02 sensors does an 04 Mazda 6 have
2 one upstream and one downstream.
The Mazda 6 oxygen sensor monitors the exhaust system, specifically managing the expended gases. On a Mazda 6, and most other cars, the oxygen sensor can generally be found on the header pipe, sometimes varying between years and models. Follow the exhaust pipe from the header you will find the next one. 2 in total.