Fire up and Get going

Fire up verb - To rouse to strong feeling or action.

Get going and fire up are semantically related in stir up topic. In some cases you can use "Get going" instead a verb "Fire up", when it comes to topics like stimulate.

Get going verb - Begin or set in motion.

Fire up and get going are semantically related in excite topic. Sometimes you can use "Fire up" instead a verb phrase "Get going", if it concerns topics such as stimulate.