If your Craftsman tool has been sitting in the garage for a few months collecting dust, chances are that the components have simply gunked up with rust and debris. If the throttle lever isn’t moving, then you could be dealing with simple rust. Spray some lubricant around the lever and slowly ease it back and forth until it is lubricated enough to move freely.
Dirt collecting on the cable is another culprit that can cause issues. Use a basic degreaser spray on the cable to help free it of any dirt and debris. After you spray the cable, jiggle the throttle handle back and forth a few times to work the spray into the cable and then wipe off any excess.
A rusty cable is similar to a dirty cable except the rust has locked it in place. Just like with the throttle handle, you will need to apply some basic lubricant to the cable, jiggle the handle back and forth a few times to work the lubricant into the cable, and as the rust becomes lubricated it will finally break free and allow you to move the cable.
Sometimes if you have left the machine parked for an extended period of time with the throttle in the maximum position the cable will naturally stretch out. You will need to adjust the throttle cable to take the slack out of it. Move the throttle back to its lowest position and fix the adjustment under the handle where the cable runs into the handle. Simply use a screwdriver to make the adjustment and make the cable taut again.