L86 Lean Bank 2 issue

[Snowhunter87]

Hey guys,

We swapped a 2017 L86/8L90E into a 2008 Jeep Wrangler JK. Got about 650 miles on the swap but we are getting a weird bank 2 lean issue and the computer is hosing the house down +30% on bank 2. Starting the jeep out cold, the STFT are dead even, oscillating back up and down together for about 30 seconds. Then the bank 2 o2 will start to climb to the point of jumping around between 27-30 for good where it never comes back down. Pulled plugs and they are sooted black as a diesel exhaust pipe. Same with 02 on that bank.

So far, we have replaced all 8 spark plugs, both left and right upstream 02's (downstreams are not plugged in and deleted). Smoke tested intake and exhaust looking for leaks and everything looks good.

What am I missing here? One of my techs suggested we swap out the injectors, another guy said we need to check the o2 heater wiring circuit. Anyone experience this?

Fuel mileage is junk 10/11 mpg's, stinks like fuel, hazes out the exhaust when you hammar on it.

[kevin87turbot]

Does it have any misfires? Any DTC's of any kind?
Any exhaust leaks on bank 2?
I'd also check for intake leaks.

If there isn't any mechanical issue, it's certainly possible that the oxygen sensor on that bank is bad or possibly the wiring to that sensor has an issue.

I just went through this same issue with a 2018 L83 swap into an 85 Blazer. It ran great when I commanded open loop. Ended up the oxygen sensors were bad...on both banks.