So I was driving the other day and I got a CEL. When I got home I read the codes and I have the following: P0141, P0161, and P0140. These are all oxygen sensor codes for the second bank sensors. The funny thing is I replaced all 4 sensors about 5,000 miles ago. Is there a possibility that they kicked the bucket this early or do I have a different problem to deal with. Any help will be appreciated.

PS I have 168,000 miles on the truck

 

Check and see if oil from your valve cover has leaked into the 02 connections, if so fix your clean and clean your connections.

 

Thanks Mike, I will check on them in the morning. Arent the rear sensors further back though. I know my valve covers are leaking a bit, but that would seem to effect the front ones, not the rear. Could oil covered front sensors cause mishaps in the rear.

 

My mistake, but check them anyway.
You should have a 1 year warranty on the 02's from the supplier, if needed.

 

But yes you can purchase a brand new oxygen sensor that is bad or yes a oxygen sensor can fail that fast. Now have you had any problems prior to changing them or was it just as preventive maintenance?

 

They were getting old and I was throwing codes so I replaced them all. First the front two, then the rears a few months later. I took Mikes advice today and cleaned the connections. After a few hours of driving, accompanied by a number of on/off cycles (going into stores and such). I havnt gotten any codes. Perhaps they were dirty/loose. I wanted to ask if it's a good idea to put dielectric grease on the connectors. I havnt in the past but I do use it on the plug wire connections so I figured it might help here. Thanks for the help

 

Oh and one more thing I failed to mention.... The sensors I got are OEM equivalent bosch ones not cheap imitations where you have to splice in the connectors.

 

Okay great news!!! Yes dielectric grease is good, and dirty or loose connections will interrupt any connection and cause problems.