Welcome aboard! Glad to have you here.
Any codes? If you don't have a code reader or tuner that can read them, take it to a parts store; they will read them for you for free. Then simply put that code in the Google search box (or search them on this site) to obtain good info on what the problem is, and in most cases, what the suspect components are.
Cleaning the throttle body is a good place to start as well. You may have a bad COP (coil over plug), but this will most likely have a stored code to indicate that.
I'm a firm believer in not tossing parts at a fault; eventually you fix the problem, but it gets expensive.
Get the codes read, then post them here and/or search on them in Google.
Give an answer, they learn for the day; suggest a search, they learn for a lifetime.
2005 F150 STX Regular Cab (4.2 liter V6)