35th camaro

having bucking and surging problemes and wanted to see if i'm having any misfires with my scanners, i have new snap-on and otc and both are freezing up on me,on the same screen the rpm are good but misfire for all 8 cyl. seems to be frozen, sometimes i will get a misfire or 2 then freeze, even misfire cycle if frozen on a #, when i go to other screen all other data is good. is it possible that the tune has effected this option, i know i dont get any misfire codes. putting car away in 6 days for season and would like to figure something out.