We need to start with the basics if you have not already. Let's get the codes pulled so hopefully it will limit it down and tell us which cylinders are the issue.
Next I included so guides that you can review to help identify and then fix the issue.
Let me know after you have the codes and read through this material. Also, let me know if you have done anything to attempt to address this already. Lastly, let me know which engine you have. 3.0L or 4.0L?