Here is a little story with a question at the end. I had a cylinder missfire- 301, #1 cylinder. I had an old coil so installed. Same code. Bought a plug and installed. Same code. Pulled the injector and cleaned and install. Same code. Never really bad miss just slight. Goes away after 3-4 minutes warmup normally... Since it goes away im thinking maybe maybe loos of fuel in the rail. I pull the regulator and pressure test- o.k. I put a gauge on the rail and have 40 psi running, but drops off slowly when shut down.. Now im thinking leak at the pump in the tank. I pull the filter and put the gauge on that. start pump a few times and have 44 psi. Let it set and it drops to 20 psi in 30 minutes.... o.k. i think i need a pump someday. Take off for work today and COMPLETE failure of one cylinder missfire ! WHAT?? DRive 60 minutes to work and back with it bucking and running on 7 cylinders. Check the code when i get hom... 302 !! #2 cylinder missfire ! Change out the #2 coil with a spare and problem solved! I have heard some talk about missfire caused by "the next cylinder" to the one giving the code. I always assumed you ment the next in line to fire, not the next in physical location on the block... who has had this before ??

 

Pressure drop in 30 minutes is not a problem. The pump is running all the time.
The pump/system only has to hold pressure long enough once you turn on the ignition, to pressure charge the fuel rails for starting.
COP coil ignition is independent of one another. One has no effect on the other either next to fire or next cylinder.
The earlier coil paks are subject to that because of how they work in cylinder pairs.
Each of your coils and injectors has seperate drivers in the PCM and seperate leads in the harness.
Maybe the first coil you replaced, with another bad coil.
Also look at the boot if reused.
It is remotely possible to have a bad valve /seat in that cylinder that seals up after the motor warms up or even a valve that hangs up. That is tested for with a leak-down test and listening in the intake and exhaust for escaping air.
Listen to the exhaust for the miss and if it goes away. You should hear a piz-piz-piz etc when the miss occurrs.
Good luck.