My 06 tacoma is misfiring

I have a 06 Toyota Tacoma out of the blue about a month ago it started not taking gas and running horribly the more gas you give it, it will not take it just almost like it stalls it won't do anything until letting off the gas only being able to get it no more than a quarter of pedal. It's backfiring and only able to give it just a little bit of gas in what you call a sweet spot in order for it to run right or just run not right. I replace the spark plugs check the coil packs and also put a new mass air flow sensor and throttle positioning sensor. After doing this the trust is running better but it will all the sudden go back to doing what it was before and if I cut the ignition off and turn it back on it will start running pretty good once again. When I start the car up if it was up to 3000 RPM and fluctuates back and forth down to 500 RPMs all the way up to 3200. It's Butters app low speed but on the highway 50 to 80 miles an hour it runs great with no problem but as soon as I let off the gas it's like the engine stalls and didn't all the sudden jumps back up it's very weird any suggestions would be great

 

Welcome to TacomaWorld Jason

 

Thanks

 

Welcome to TW!

 

Welcome!