I have been trouble shooting an 0420 code on my rig. Not wanting to replace the cat if it is fine, I wanted to do some troubleshooting.

I removed the two o2 sensors on the vehicle passenger side.

I moved the two sensors from the driver side to the passenger side.

I put 2 new sensors on the driver side.

I found that the driver side rear o2 sensor was not tightened down like the other three were. This may have been the cause of the original code.

However, here are some of the readings I am getting on my front sensors now:

BANK 1
Rich to lean sensor switch time Bank 1/S1 = Value .064 sec / Max .14 sec
Lean to Rich sensor switch time Bank 1/S1 = Value .032 sec / Max .204 sec

BANK 2
Rich to lean sensor switch time Bank 2/S1 = Value .024 sec / Max .144 sec
Lean to Rich sensor switch time Bank 2/S1 = Value .016 sec / Max .204 sec

The voltage sensor values for each bank are fairly close.

Not sure what the TID $70 and $71 read, but they are 119/119 on Bank 1 and 132/146 on Bank 2.

I have no experience dealing with these numbers. I would say that the new sensors I put in are operating slower than the old sensors. I would think that is a bad thing. Is it enough of a difference to pull the new/slow sensors out and return them for a different brand? I would think that the old sensors with 110,000 miles should be the ones with the slower responses.

Does anyone that knows what these numbers mean, have any suggestions? Or am I correctly intepreting the numbers?

Thanks for any help.

 

Have you replaced your fuel filter? May be restricting fuel flow???? i don't know, just a thought.

2003 Avalanche 1500
4X4
128,955 miles