I need an idea as too where both the upstream passenger side o2 harness run behind the block ?
I bought this 97 4.3 v6 with one driver side o2 upstream installed in the Y-pipe . I welded one more bung on passenger side after the cat . Yet I called GM dealer and all aftermarket cats show 4 o2 sensor ports. I am missing the one that is directly in front of the CAT.
One of the Harness is not there visibly at all for the other upstream o2 ?? This is boggling me because I was under the assumption it was a 3 sensor truck .
Was this a option for 3 o2s based on some feature or certain vins in that era . Or is there no doubt the harness should be there .
The cat is not original it was replaced with a bad off brand some years ago ...but they never added the Downstream o2 port of let alone the missing 4th o2 upstream port
The OBD Live date feed shows 4 o2 sensors while truck is running one has no Movement
Any help will be appreciated.
Alao need help with my other Issue and question about the egr tube on my other post
Thanks
I bought this 97 4.3 v6 with one driver side o2 upstream installed in the Y-pipe . I welded one more bung on passenger side after the cat . Yet I called GM dealer and all aftermarket cats show 4 o2 sensor ports. I am missing the one that is directly in front of the CAT.
One of the Harness is not there visibly at all for the other upstream o2 ?? This is boggling me because I was under the assumption it was a 3 sensor truck .
Was this a option for 3 o2s based on some feature or certain vins in that era . Or is there no doubt the harness should be there .
The cat is not original it was replaced with a bad off brand some years ago ...but they never added the Downstream o2 port of let alone the missing 4th o2 upstream port
The OBD Live date feed shows 4 o2 sensors while truck is running one has no Movement
Any help will be appreciated.
Alao need help with my other Issue and question about the egr tube on my other post
Thanks