ok so i replaced my o2 sensor like 3 weeks ago and now im getting this code again....

reason y i searched is for some reason when its in the 40s or lower, truck doesnt want to start easy and wants to die when i come to stops and wants to die when i try to go...

anybody got any ideas???

 

First of all, did you reset the computer after you replaced it to erase that code?

Now that the obvious is out of the way, there is always the possibility that you got a bad sensor. See if they'll warrenty it out and try again.

A more likely possibility is that there is another bad sensor causing the problem. Besides the stalling, how is the truck driving? Also, are you getting code 51 or 52 as well, or just 21.

 

12 21 and 55 r the only codes i get,

yes i disconnected battery for bout 30 mins to reset,

the truck honestly doesnt feel like it did before it broke down 5 years ago...(just recently got it running again), i started it up every couple months while it was down to stop motor from locking up

replaced rotor,cap, plugs, wires, shocks, clutch, o2 sensor... since i got it running again...

the truck really doesnt feel like its running to full potential, when i punch it it just feels like it doesnt have the power it use to, kinda lags before it goes...

it acts worse when the whether is cold and rainy

 

I just have a feeling the MAP and/or TPS and/or IAC is somehow involved with your problem.

Have you checked the o2 sensor wires to make sure there is continuity and proper voltage? We have the wiring diagrams available in faq2 or a reference.