Intermittent power loss and light ticking

Hi everyone, im having an issue with my 99 v6 tacoma.
When the truck is cold it accelerates as it should, the motor purrs and I can pull steep grades at 80 mph no problem in 4th gear. Once it reaches operating temp it periodically loses power , not alot but enough to where when im pulling those same steep grades ill slowly drop from 80 mph to 73 -70mph by the time I reach the summit. Accompanied with this power loss is a light ticking sound, the truck goes from sounding like the flowmaster purr to an old Chevy with an exaust leak. When this happens if I floor it, the truck will accelerate in stages, it'll bog, than pick up a little bit until im at 3500 or so and it evens out but it just feels low on power. Its not a smooth power delivery.
Also when this happens if I throw it into neutral the rpms will stay high until I apply brakes or blip the throttle.
Iv done alot to this truck, threw parts at it trying to get it to run as close to perfect as possible. Admittedly I skipped the diagnostics and through parts at it because im kind of an idiot and every time I did, I thought I fixed it but itd end up doing the same thing. So here's a list of stuff I did in the last 10k miles.
Denso injectors
Oem iac valve
Denso mass air flow sensor
Timing belt /water pump
Cheap oreilly coolant temp sensor(yeah that might have f***** me?)
Oem tps sensor
Oem pcv valve
Denso crank sensor and pigtail(that actually needed done)
Knock sensors (oem)&pigtail also oem
Intake manifold and plenum gaskets
Fuel pump
Plugs/wires/coils all denso.
Denso coils are
I replaced the vaccum lines as well.
I believe that's it, im at a loss here. I know how to replace parts, but Im not knowledgeable with diagnostics.
I know my fuel trims aren't ideal, long term is spiking from 12-17. short term goes from -3 to positive 3. Maybe even more of a differential. Ill have to graph them again tomorrow because im going off memory at the moment and I could be a little mistaken .
Im open to ideas, honestly id rather spend 1000 bucks throwing more parts at it instead of bringing it to a mechanic and spending 1000.
Mainly because I tried that, I went to 3 different shops and they've all done sub par work and the problems dont get fixed and I end up doing it myself in the end. I live in southern oregon and iv yet to find a decent mechanic. Anyways, Sorry for the book. I hope to hear some ideas. Thanks guys. -Bill

 

Could this be a trans issue and not the motor?

 

Have you done a compression test to see how worn your engine is?

 

Does your CE lite come on and off when taco bogs?

 

Hey guys, no haven't done a compression test, have a manual transmission so I doubt that's the cause. And no cel. I had a code for knock sensors and the cam sensor , that's why I replaced those parts. I just put in new ngk platinum dual electrode plugs. Old plugs all looked consistent with each other, slightly ashy,

 

Try fuel filter…….didn’t see tht on your RR list


Strange, I guess bc of summer heat(?)

there have been a rash of FF and TPS threads last 2 weeks

 

Shit, i forgot to mention that I did also do the fuel filter. I did it three times actually.. once with a crappy autozone duralast, than with a wix, which was a step in the right direction and finally I went with an oem filter from yotashop.
After trying to save a couple bucks with filters that I should put the oem filter in so I could rule that out.

 

I also put in the old coil packs just to see if it would run better and it seems like it is. The old coils were genuine toyota densos, the ones I just removed were aftermarket densos off yota shop. Im not sure if the new plugs helped but it does seem to run smoother with a little more pep.
It could just be placebo effect, when im cruising through town and I let off the gas I still get a rough decel, it almost sounds like an exaust break. If I can't figure this out I might just take it to toyota after fire season and have them thoroughly test for vaccum leaks / do diagnostics to figure out wtf is up with this thing. In the meantime im open to any and all suggestions, I really appreciate it.