1996 S-10 Pick up Question

[2003YZ250FRACER]

My code reader read PO140 which says that there is no activity detected ON O2 sensor; bank one sensor 2.

Does that mean that its the sensor after the cat? Im not exactly sure and wanted ta find out before i spent the money on the sensor. Its not that big of an expense but im goen ta school and money isnt the easiest thing to come by. One of the sensors is $25 and the other is around $60 so im tryen to avoid buying both. Any help is appreciated!

[astrnaughtwanabe]

If you plan on keeping that truck i would buy a chilton from the autoparts store, i know you said money is short but it will save you money and headaches later if you keep the truck and also on my 95sonoma you had to undo the motor mounts to take out the starter and im sure yours is the same way so be prepared with money to have someone do it, get ready for that pain in the ass but here is alittle of what my chilton suggested.

1. Perform a visual inspection as follows:

a. remove the senor from the exhaust, if the sensor tip is black/sooty = rich

if the tip is white and gritty = internal antifreeze leak

if the tip is dark brown could indicate oil consumption

and it has pictures, pretty much if you can just wipe off the brown then its something else but all 3 of those can cause the sensor to go bad, and it tells you a way to test your sensors with a voltmeter but i'll be here all week typing that, but as far as the code itself talking about bank one and stuff, there isnt much to help me with that... if you dont want to mess with that, fix the cheaper one first and hope

[loufish]

Yes, sensor #2 is behind the cat, also known as the down-stream O2.

Most O2 sensors get "lazy" meaning they are slow to respond to changes in the air-fuel mixture. If the code is no voltage at all, check your wireing before buying a sensor, it could still be the sensor, but don't buy one yet.

Another trick is to switch the 2 sensors IF they have the same connections that way if the sensor is bad you will get a new code about the up-stream sensor being bad.

[2003YZ250FRACER]

Ok well i did a lil experiment today. I pulled the #2 sensor cleaned up with brake clean reinstalled it and so far so go. No check engine light. Yet.

But i wonder how long it will last????

[Rip Wheeler]

My code reader read PO140 which says that there is no activity detected ON O2 sensor; bank one sensor 2.

Does that mean that its the sensor after the cat? Im not exactly sure and wanted ta find out before i spent the money on the sensor. Its not that big of an expense but im goen ta school and money isnt the easiest thing to come by. One of the sensors is $25 and the other is around $60 so im tryen to avoid buying both. Any help is appreciated!

Yes, B1S2 is the one after the cat. No activity means its probably a failed sensor or an open wire. The only purpose for this sensor is to let you know when the cat is degraded by 60% or more. It has no affect on engine performance.