diagnosing a bad injector

[c10 custom]

hi guys i have a question about a 2000 chev 1 ton 4x4 old style model
its a 454 engine and i changed spark plugs wires cap and rotor and it still has miss so i hooked up my mac mentor scan tool and found that number 4 cyclinder has a misfire but no codes present the scan tool data reads
misfire current cyclinder number 4 readings go from 2-190 counts and back and forth so i was thinking bad injector on number 4 any help would be great thank you

[bighaas79]

Some scan tools have an injector drop test function don't know if mac has that or not. Always used snap on or factory equipment. If it does it's a very quick way to check if injectors are firing correctly. If you have a lab scope available you could always do a current ramp and voltage pattern as well if you know what you are looking for.