O2 Sensor - Peculiar Behavior
 

'02 3.0 - 2 new ex. Manifolds & new 3rd cat - New EGR & PCV - all (6) New coils / plugs - all (4) New O2es - Confirmed no vacuum leaks - 85,XXX miles

All recent work re: front cat that puked into downstream cat = limp mode = towed home

I've done a good deal more work than above, but a case "while I'm in there" and gen. maint. to hopefully 're-bulletproof' the wife's pet SUV. And important to note there have been NO CODES since all this work. So, running in the blind with the issues below.

I have a very unusual issue and no info on here or general search. From dead cold the (brand new) Bank 2 O2 takes over 1 minute to move from 0.0, and then only to peg on 0.01 for the next 1 1/2 minutes. Now this in contrast to the Bank 1 sensor that immediately begins and continues cycling consistently from 0.1 to 0.9 and back. If I don't touch the pedal the Bank 2 will gradually increase its + & - range over the next few minutes from ~0.08 to 0.20, then cycle 0.10 to 0.35, but it will take over a total 5 minutes from starting for the Bank 2 to move the full range and as rapidly as Bank 1 back and forth from 0.10 to 0.90.

I've recorded the same thing 3 times, but if I hit the gas along the way then it seems to speed up this 'slow wake-up' process to full range readings by a minute or two. The more important question for me is why such stark difference in readings for the two banks, both having brand new sensors - AND brand new ex. manifolds.

I should mention I went and ordered and installed a 'replacement brand new' brand new sensor in Bank 2 as I though the other was defective. When I saw basically the same behavior repeating I figured I basically wasted $35, but it removed a variable, and it pretty much eliminates either one as being 'defective' if that helps in replies.

Additional operating details: 60# FP, Starts up fine and idles to 750 quickly, but first couple minutes a slight tiny INTERMITTENT miss in idle until the second O2 starts reading a range other than just pegged in the 0.01 - 0.06 area. Once warmed up, then perfect idle and perfect acceleration. All this is not keeping my wife from using the little spud again, just using it more confidently. Any leads on the weird reading patterns?

Full disclosure - I posted this in the Ford (Escape) group as well, and share any feedback.