bad 02 sensor

i have a 2002 3.4L V6 4dr TRD. check engine light is on, ran code, say 02 sensor. any body know how to deterime which one? when i get out of the truck is smells like it is running rich. also anyone know the cheapest place to buy the 02 senser?

 

What code was it?

 

x2 that that code should tell ya which is bad...but strongly suggest doing yourself a big favor and replace them all. If one's bad the others aren't far behind, or probably are bad just not enough to trip a code yet.

 

Most likely the front one.... as they're closer to the hot gasses of the engine.

Did you get the codes pulled from the dealer? They should be able to tell you which sensor it was....

http://www.lieblweb.com/o2replacement.html