Where and how many oxygen sensors are on a 2000 Mazda MPV?

Answer 1

There 4 total, one before the catalytic converter (upstream) and one after (downstream). Same for both sides. And the catalytic converter is built into the exhaust manifolds, one per side, so all 4 are technically in the exhaust manifolds. Now aks how easy they are 2 change. Not very. The two after the catalytic converter are OK to get at from below the car. The two above are tough. I took out the rad to get at the front one. Still trying to figure out how to get at the rear one. Any suggestions would be appreciated.