If you have a 94 your best bet is to go with the factory kit P/N 89465-60110. Here is a web link that has some info on the factory O2 sensor recall, plus it has step by step instructions on how to install your new sensors. http://www.risingsun4x4club.org/uploads/Snowrun/1994 fzj80/1994 Repair manual/Service bulletin/T-CP-SO2-0162-W.pdf
Here is a photo of what comes in the factory kit, less the 4, round gaskets, and head pipe lock nuts, those are extra cost items. In my case i needed those extra items to replace my O2 sensors. That's because i had to remove my cats from the truck to install my O2 sensors.
I had to replace my rear o2 recently and read a bunch of old threads before doing so. Denso was the general consensus based on my research, and that's what I got. Pretty cheap on Rockauto.com. Worked like a charm.
My research also concluded that bosch just don't work right with our trucks.
Have you tried cleaning them? I was throwing an O2 sensor code recently and multiple sources said they rarely go "bad" and to try cleaning them first. How to clean an O2 sensor? Too easy. The below worked perfect for me and saved me a nice chunk of change.
1. Buy a jar of your favorite salsa or queso and some tortilla chips.
2. Eat all of it.
3. Clean jar.
4. Remove O2 Sensor(s).
5. Place sensor(s) in jar leaving pigtails dangling out top of jar.
6. Fill jar with enough gasoline to cover sensor(s) up to the mounting flange.
7. Let sit overnight, at some point, swirl jar to help loosen sediment.
8. Remove from jar and scrub elements with brass brush, you'll be shocked to see they look brand new. I let them sit for a couple hours to make sure the gas all evaporated.
9. Reinstall, clear codes, and give it a shakedown run.
Sounds kinda hokey but i havent seen a check engine light in a couple months now since giving this a shot.
