Hey guys !!!! My srt-6 has 110k miles on it. I have needswings dual intake, needswings manifolds, euro charge 65mm pulley and tune. Recently after driving the car after it warms up I get small shaking and misfire. What can cause such issues and where should I start looking at? Forgot to mention misfire is in cylinder number 4

 

Easy first thing to try : swap that coil pack and wires with another cylinder.

 

If my car is low on gas and sit for about a qeek it misfires on 3 cylinders,but after I clear the codes and restart the car all is well.