2005 Ford Focus Gas pedal sticking

Hi,

The gas pedal on my car is hard to push most of the time, and sometimes I have to use a lot of force to push it down. I have googled this and most of the results that I am getting are referring to the throttle body. How do I know if it just needs cleaned or if it needs fully replaced? I am planning on using some throttle body cleaner and cleaning the butterfly valve and throttle plate, but what kind of throttle body cleaner do I need for my car type?

Thanks!