middle cylinder on passenger side is #2 on Fords
Just do this before going to injectors.
Disconnect coil pack wires, 4 wire connector, so no spark
Crank engine a few times
Check spark plugs #1 and #2 both should be equally wet with fuel
#1 is the assumed OK cylinder so will be wet with fuel
#2 is the dry one if injector is indeed the problem.
Just got a misfire on my 4.0l yesterday, came and went throughout the day, cracked insulator on spark plug electrode, checked out OK, had to look close to see the crack.
Spark plugs are funny that way, compression and heat can make them intermittent.
And just a heads up, computer is pretty good at IDing a problem, but it isn't perfect.
P0302 is what the computer "thinks", it could be #6, P0306.
2 and 6 are matched pair cylinders/pistons, so are 1 and 5, and 3 and 4
So 2 and 6 are both at TDC at the same time.
Just give #6 a look