I’ve changed plugs, wires, and coil packs. No vacuum lines seem to be loose/cracked. This is my first ranger so I know little about these motors. Any ideas or things to check?

 

Is the check engine light on? Whether light is on or not, use a scanner and see if there are any codes evident. (Autozone, etc. will check for any codes for free.)
No codes? With engine idling, carefully spray a small amount of carb cleaner (using the plastic nozzle extension tube) at every vacuum hose junction point, including the large hose at the brake booster and the PCV. Spray around EGR and along intake manifold gasket. Don't forget to check green and red rigid plastic vacuum lines (one connects to the fuel rail pressure regulator and the other goes to the EGR valve. Trace each to the other end and spray there also. Careful... these are rigid plastic lines and can split or break.)
If at any point the engine revs, that means it just sucked in some carb cleaner, and that would be your vacuum leak (or one of them, anyway.)
Dirty fuel filter will cause problems, also.
Try these things and write back...