Thought I fixed my miss, ‘97 5VZ

So while I had the truck down for the timing belt, water pump etc; I put in 2 new OEM Denso 02 sensors. Long story short, the truck barely ran after the TB install and the cause ended up being a broken tooth on the crank cog/ gear (my fault). Got the truck back together again and it ran smoother and stronger than it has for at least the last 8 years it’s been in the family.
Before the 02 sensors and TB/ WP job, the truck had an intermittent and random miss/ sputter at full throttle. It wouldn’t always miss at WOT, and rarely missed if rpm was between 2000 and 3000 at WOT.
It was always guaranteed to miss if WOT below 1500 rpm or so. It also almost always missed at WOT above 3500 rpm.
The CEL was a p0420 02 sensor code.
So a few days after the 02 sensor replacement (and running so well) I dip heavy into the throttle at 1400 or so and she falls apart missing. It also missed above 3500 once again.
Truck has new 2 new Denso 02 sensors (correct for manual trans), dual electrode plugs, new plug wires, new fuel filter, new Walbro fuel pump and everything that comes with the TB/ WP job. Do you all have any opinions about other potential causes?
The truck ran so perfectly after the 02 sensors (old ones were knockoffs AND ancient) at WOT and the CEL went off I just KNEW that fixed the problem. I was very wrong unfortunately. Thanks!

 

Clean the MAF and the throttle body.

 

Thanks for the response! I forgot to add the MAF is spotless (hosed it with MAF cleaner a month or so ago), but I haven’t cleaned the throttle body. Could that cause issues at WOT?

 

Yes, I believe so.
Let's get some other opinions
@gearcruncher

 

@Bishop84

 

Sounds like a MAF or a clogged cat.

Easiest way is to swap with another 5vz if you know anyone with a good maf.

With clogged cats easiest way to free it up is to remove the 2 up stream o2 sensors and drive it to see how it feels.

It could be fuel or a number of other items but its where I would start.

Throttle cable style 5vz's don't really stumble if the plate is dirty.

 

Thanks you guys! I’ll pull the 02 sensors and zipper them for a test. The only thing that makes me wonder about a clogged cat is when the truck doesn’t miss, it’s got seemingly full power. The 1st day I drove the truck after the new sensors it ran an 8.9 second 0-60.
It ran that well for about a week before the old miss issue came back. It’s never run that well for that long (without missing) until changing both 02 sensors. It’s bizarre (coincidental?) the truck ran like new for a week after the sensors when it hasn’t run like that for years, but then it suddenly is back to missing.
Can a clogged cat sometimes allow full power and other times not? I’ll separately swap in the MAF from my ‘02 taco for a test. Thanks again!

 

Do the stock injectors ever wear out or give any issues on these engines?

 

What are you using to scan for codes ?

 

This is what I’ve used, and before I got it 2 different advance autos scanned and got the same code.
I will say it misses much less frequently now after the new sensors, made a pull to redline last night with no hiccups. Before this it would miss probably 8 times out of 10 at WOT above 3500