Po133 O2 Sensor Circuit Slow Response (Bank 1 Sensor 1)
 

Does anyone know if this is really an O2 sensor and if so which one (where can I find it)?

David
98 F-150
4.6 liter

Sounds like it.

How many miles on your truck?

92000

I read somewhere that you should replace all your O2 sensors (4) at 100,000.

might be an easy fix

On my '97 5.4L bank1, sensor 1, is on the passenger side closest to the engine. I had the same code and replaced just that sensor. As for replacing them all, at $50 apiece, I think I would just replace them as needed. The one I changed was a serious "bitch" to get to.

firmin,

I was just reading somewhere that when you get that code (slow response)
you should replace BOTH O2 sensors in that bank. In your case Bank 1 sensors 1 and two. If you don't the PCM may read the old sensor as being slow (compared to the new one)

Good Luck,

Bill

i believe the...
 

up stream sensors are the ones that take the beating and the downstream sensors(past the cats) rarely need to be changed