Hey everyone, I have a 2002 5.3 swapped into an 89 Silverado. The truck runs great and mostly everything works, with the exception of the o2 sensors. For some reason, I keep getting the codes P0134 and P0154 which is "o2 sensor circuit no activity detected, bank 1/2 sensor 1". I've tried replacing the o2 sensors with brand new ones. Still get the code. I even just got my PCM back in the mail. Had it swapped out and re-flashed. Still no luck. So that leaves the wiring. I've checked that out too, and everything seems fine, but since I've replaced everything else, it seems that the problem would be in the wiring. I'm running out of ideas.

Can someone maybe post up a diagram of how the o2 sensor wires are supposed to be run and what pins they go to on the computer? I have the isolated ground o2 sensors.

Thank you for any help. I'm to the point to where I just want to get rid of the darn thing already. Or swap engines again...

 

Since you know what type of sensors you have, check that they're grounded correctly. There are only 4 wires, 2 being grounds, one 12V for the heater, and one signal wire.

I think lt1swap.com has diagrams for both styles.

 

http://lt1swap.com/99-02_vortec_pcm.htm you should be able to see where the go using this pin out, the grounds are specific to each side as well.