o2 Sensor Question

My truck is throwing a code (PO420) I was told it was the Upper sensor. I was wondering if someone could help me find where it is so I can replace it or if there is a more simple solution. I was also wondering if this is a common problem with the 02's. Thanks.

 

this
http://www.4x4wire.com/toyota/4Runner/tech/O2_Sensor/
http://www.tacomaworld.com/forum/1st-gen-tacomas/142451-rear-o2-sensor-done.html

just do it by the steps
order them from rocauto in the offical vendor list AND GET THE DENSCO nothing fancy or $$ for these trucks or they will let you know.
i would get both so i would not have to get back under there if and when the other one goes out and it will
get some good bold blaster lube and practice getting under the truck for a few day to looses up the bolts while the parts are coming when its cold give them a blast, drive it and then repeat for several days will save you from a lot of swearing. they can get very rusty!

 

sensors dont just go bad. something cause it had to go bad either from too much contamination from fuel or coolant or from a weekend warrior with seafoam or lucas. pull it out and check to see how dirty the sensing part is. dont just throw parts at it cause it may not be long before the new one goes out without determining the cause of the failure

 

well I am sorry but sometimes they do. they wear out just like anything else on a car over time. I had a 92 Nissan SER put 300,000 on her but at 120,000 miles I bought a socket, had to back then, cleaned it with carb cleaner, friend at Nappa told me this trick, if you car has a funny idle, and it had some carbon on it, well 3 months later at Myrtle Beach on the week of the 4th, it just died..... and i was really stupid i used the car jack to get under the car to fix it myself...and drunk..

i read this awhile back, its long..

 

Alright, Thanks for all your feedback guys today I am going to get under there and start loosening them with some lube and Im also going to replace both I do believe. I may have another question along the way but thanks again.

 

well just ask.
are you near Winchester VA? or more near the dreaded washington dc

 

Im far enough away from D.C. thank god and I am kinda close to Winchester. I am in Fauquier, well Warrenton. I am in Winchester pretty often I got a lot of buddies up in Berryville.

 

when my uncle was in business, we used to sell to sunbelt rentals, and man i can't count the trips I made that way up 29 and interstate 81 but I always enjoyed countryside! Esp. in the fall.

 

ttt

 

Oxygen sensors are considered 100K replacement items. So no defects there. I'd do both. Probably go with OEM(Probably Denso) instead of Bosch or NGK. Check Rock Auto once you have the exact part number.