O2 readings for 4.8

I wish I had found this site a week ago!
I also had a warm start problem, which turnout to be the fuel reg.
During my troubleshooting, I bought OBDScan from Harrison R&D.
It appears that the Bank 1&2 O2's are working, but when the engine is at normal temp the Bank 2 O2's stay at .8vdc, indicating a rich condition is this normal for the 4.8?, I checked a friends 03 with a 6.0 and all 4 O2's seem to be working find?

I also had a warm start problem, which turnout to be the fuel reg. During my troubleshooting, I bought OBDScan from Harrison R&D. It appears that the Bank 1&2 O2's are working, but when the engine is at normal temp the Bank 2 O2's stay at .8vdc, indicating a rich condition is this normal for the 4.8?, I checked a friends 03 with a 6.0 and all 4 O2's seem to be working find?

I work at a Pontiac dealer and a few weeks ago we had a truck come in for a fuel press reg and the O2 reading that you speak of were on our truck to. All we can come up with is that the reg was leaking into just that bank. .8V or 800mV is the O2's way of saying way to rich. I bet you drive the truck a few more days and hook the scanner up and look at Bank 1 O2 1 and it moves around like a superball. It should go between .2-.8 back and forth about 2 times a second. (Depending on how fast the communications are with that scanner) :bigthumb: