I have a 2004 Gto! When i start it it wil sputter to 100 rpm them it will level out to normal after a few seconds. Put into gear does it again

I’ve replaced throttle body,mass air flow sensor, throttle sensors and still no change. I drive it and it will sputter and misfire. I drop to a lower gear and step on the gas it will come out of it. What am I missing to replace to make it stop doing this?