cylinder 2 misfire p0302

[acko]

need help with a misfire cylinder 2, about two week ago got a service engine soon, scanned it with obd2 got p0302. changed all the spark plugs and a coil 2. the car was fine for two days and then again the engine light came back. now i changed the cylinder 2 fuel injector and same situation is happening. when am driving the car around 40 mph "higher gear, lower speed" the vehicle start to "jerk" only when am having my foot on the gas. don't know what else it could be, please assist ohh yea the car is,,,

2004, bmw x3, 3.0l, winter package.

also, what is the firing order..

thank you..
sifet