There are two; the price may vary by year. As an example though, for a 2010 the upstream (before the catalytic converter is about $130, the downstream (after the converter) is about $100.
These parts are expensive but don't often break/wear out. Make sure you don't have another issue. If you are getting an OBDII code for the downstream sensor (such as below efficiency threshold) , its probably a problem with the cat, (which don't often break on their own) caused by another issue (rich fuel mixture, dead cylinder).
A 2000 Ford Focus oxygen sensor diagram can be obtained from most Ford dealerships. The diagram can also be found in most Ford repair manuals.
Where is the coolant temperature sensor on a 2001 ford focus?" Where is the coolant temperature sensor on a 2001 ford focus Where is the coolant temperature sensor on a 2002 ford focus
It is located before the Calaytic converter
Where is the temp sensor on 2000 ford focus zetec engine
Where are the Bank 1 Sensor 1 oxygen sensor on a 1998 ford explorer?
It is most likely your oxygen sensor
unplug from loom, get big spanner and unscrew from exhaust. refit in reverse
In the duct between the air cleaner and the engine, with a bunch of wires, on a plug, hooked to it.
cooling sensor for 2004 ford focus zts radiator
The 1981 Ford Crown Victoria does not have an Oxygen sensor.
where is the engine mangement temp sensor on a ford focus and how is it fitted
Remove the vacuum hose from the oxygen sensor. Remove the oxygen sensor retaining screws. Reverse the process to install the new oxygen sensor.