P0171 and P0174 codes

You are on the right track but to get a confirmation faster (that you fixed it), take your scan tool and delete the codes and see if they come back. You can also reset the check engine light by disconnecting the battery a couple minutes. If the problem persists, check for vacuum leaks and replace air filter. This is a common problem on Ford trucks, but not real serious.

Check the PCV Tube Elbow, located at rear of intake manifold, or the tube itself for breaks or tears. This is a common failure on these, and an easy and inexpensive repair.

Another is the intake manifold isolator bolts, and while you are in there also check the the 2 metal wire things in the back and make sure the plastic clip on still in place