I'm preparing to change my O2 sensors. I have found 1 under the truck in the exhaust pipe on the passenger side.

Does anyone have a picture/diagram that shows the locations of the sensors?

1999 4.6L, automatic, Scab, if that helps

Thanks,
Curt

 

the two sensors that you need to change are in front of the cat. converters right after the exaust manifolds the other two after the converters do not change the operation of the engine or computer they onl monitor the operation of the converter. I would recomend bosch prmium or oe motorcraft for replacement. They will make a big drivabilit differance even if they are not putting the check engine lt on. As they get old they become slow in reacting to the mix change.

 

do yourself a big favor and remove both plastic inner fender wells.
the O2 sensors will be in plain sight. no need for special tools and the connectors will be easily accesible. it takes about two minutes to remove each fender well.

 

I got my eyeball on them last night; funny how things hide in the open! I had read other posts that recommended changing them at 50K mile intervals and will do so when we need to. Right now, nothings broke and I shouldn't fix it.

Thank you both for your input!

Regards,
Curt

 

removing the right fender well also helps when removing the starter