2007 LR3 4.4L. Replaced plugs and ignition coils in May (preventative maint, aftermarket coils). Ran great until three weeks ago. Got check engine light for O2 sensors, so replaced the cats and all four O2 sensors. Then it started running rough, missing, with Reduced Engine Performance CEL. I have swapped the coils around, but issue remains. I put in a new ignition capacitor. And I just installed new fuel injectors. The battery and alternator test good.
Codes are:
Heated O2, Bank 2/Sensor 1
Heated O2 Bank 2/Sensor 2
Cyl 2, 4, 5, 8 misfire
Multiple misfire
Misfire during start (less than 100rpm)
Ignition system fail, group 2
Ignition coli B, C, E, H primary/secondary circuit malfunction
It runs and idles perfectly, then the CEL, misfire happens. Limits eng RPM to 4300.
I also removed and cleaned the Mass Airflow Sensor and Throttle body.
Where else should I be looking?

 

All OEM brands/parts, right? These are critical systems. I am confused as to why you replaced the cats though.

Have you examined the MAF sensor?

 

I did clean the MAF and throttle body. OEM injectors (rebuilt), not OEM coils or O2 sensors. Replaced the cats because the O2 sensors weren't coming out and figured I do it all at once. Ignition coils worked fine for 6+ months (no issues) and the problem with misfire started before I replaced the O2 sensors.

 

Do you have your old coils, to swap as a test. I have had hit or miss (no pun intended) success with aftermarket coils. I myself like to keep most old/working parts just for this purpose. Basically I feel with all this stuff happening you need to work backwards. You may also want to inspect connectors at the computers behind the battery for corrosion. I would also consider checking the fuel supply/pump/etc.

Some of those codes may be casualties of the root issue. Happens often. Even with aftermarket coils, it would be odd to have so many fail within a short time.