optifreeeyesolution

I have a misfire in cylinder 3 and I've replaced plugs and coils but still reads the code after deleting. when the car is nice a warm and is at idle the engine sorta just jolts a little periodically. I can feel it jump like a small pop. any ideas? maybe time to replace injectors? also on a cold start when my battery does not decide to give it enough juice until about 5 second later the engine has an extremely rough idle. but i immediately cut it off and start it up again but this time a quick start, RPM's raise to heat the engine but you can still feel those pops i described earlier. any ideas?