light up vs fire up

light up and fire up both are verbs.

Word	Noun	Adjective	Verb	Adverb
light up	No	No	Yes	No
fire up	No	No	Yes	No

As verbs, light up and fire up are synonyms defined as:

Other synonyms of light up include light.

light up (verb)	fire up (verb)
introduce light into	begin to smoke
begin to smoke	arouse or excite feelings and passions
become clear
start to burn with a bright flame
ignite