Sounds like a boost leak maybe. Check to make sure all couplers are tight and not ripped, also is your bov maybe opening a lil under mid/heavy boost, may need to tighten the spring?

What are your plugs gapped at? I doubt thats it but I had to ask.

Are you running a blow through or draw through maf setup? Blow through setups somtimes damage the hotwires on the maf since its in the direct stream of positive pressure, I know from experience as thats how my setup is.

The whole idle afr's thing is possibly from the temp sensor going bad, but probably from the main issue you have since the idle afr issue began at the same time as the main issue, right? GL dude, stupid little things like this are annoying.