As far as I know they can not be cleaned. Must be replaced.
You didn't say if it was a 6 cylinder or an 8 cylinder but it doesn't really matter because all the O2 sensors are located in the exhaust sytem and can be seen and replaced from under the vehicle.
Only one.
If your XL-7 is a V6, then it may very well have two o2 sensors, in the event that it does it will always be worht it to replace both of these, that way it makes for less headaches down the road.
If it came equipped with them when new, yes.
check that the vacuum hose is not clogged up
That Vehicle has 2 oxygen sensors.
My 1995 Ford Explorer with 4.0 L OHV has 2 oxygen sensors (Helpfull)
No, they will need replaced if defective.
Check
Have you had your 4 oxygen sensors replaced? It turns out when they replaced my oxygen sensors, they were after market parts so the service engine light did not come and gave codes even though they were replaced.
If the oxygen sensors for the 1991 Chevy 4.3 is running rich when it is warmed up it is best to have the sensors replaced. Once the sensors are replaced this should resolve the issue.
NO. there 2 different things / sensors.
Only ones that have failed.
I'm not a mechanic / technician but on a 1988 Ford Ranger there might be ( 1 ) oxygen sensor ( upstream sensor )
Well, honey, a 1999 Ford Ranger with a 4.0 engine typically has two oxygen sensors. One is located before the catalytic converter (upstream sensor), and the other is after the catalytic converter (downstream sensor). So, there you have it, two sensors keeping an eye on that engine of yours.
There are 2 heated exhaust gas oxygen sensors , 1 screwed into the outlet on each exhaust manifold on a 1993 Ford Ranger 4.0 L .
And they are expensive to replace... (i replaced one @ $400)