2007 Tacoma 2.7L P0301 Cylinder 1 Misfire

2007 w/2.7L 4 cylinder. 319,000 miles. Started to stumble a little on cold starts. Installed fresh plugs and that cured that. Then I started to get the P0301 #1 misfire code. This is also the only error code. Performance would drop so badly, it felt like it was only running on one cyl. Restart, and it would run fine. The only way I can trigger this is under hard acceleration such as the on ramp to the interstate.
I tried the easy thing first. Swapped #1 coil with #2 coil. Nothing changed, still have the #1 cyl misfire code. I Have searched all the blogs for any guidance. I see talk about sensors effecting this, but wouldn't they throw their own code?
I'm considering just pulling the intake and replacing the injectors, fuel filter, and intake gaskets. Any suggestions or input would be greatly appreciated. Thanks

 

Are your COP - coil on pack - one for each cyl. original? How about your A/F and O2 sensors? Also original? Many possibilities, including what you plan on replacing.

 

Correct me if I'm wrong. But wouldn't an O2 sensor trigger its own Error code? I did install a new A/F with the new plugs. They are the original COP's but I felt I ruled out one faulty COP by swapping #1 & #2. Thanks for the advice.

 

I mentioned it because it is a possible cause.

 

Have you tried putting a new plug in cylinder 1 and seeing if it goes away