I have a code that is reading #4 missfire. would the ignition coil pack most likely be the problem or #4 injector?
The coil pack would be the most common part failure.
Ignition System Operation
The ignition system used on these engines is referred to as the Direct Ignition System (DIS). The system’s three main components are the coils, crankshaft position sensor, and camshaft position sensor. If equipped with the coil on plug ignition system it utilizes an ignition coil for every cylinder. It is mounted directly over the each spark plug.