2007 2.7L Misterious Misfire

Hello, I have a 2007 4-Cyl with 340,000km / 200,000 Miles.

Most of the time it runs very smoothly. Once in a while at startup it misfires really badly and Cyl 3/4 misfire codes come up.

I replaced spark plugs (needed it anyways).
I swapped #1/2 coils with 3/4 coils - but codes still come up for 3/4 misfire.

I was going to swap #1/2 injectors with 3/4 injectors next but what is really weird is that when it starts up and has a bad misfire, if I shut it down and start it again right away, it runs smoothly again.

This issue never occurs while driving, only at startup. Sometimes cold start, sometimes hot start.

I am confused!

M