i have efi gv 250 when it gets hot starts stuttering backfireing . and loses power but i can keep it running but got so hot when i made it home muffler turned color. im thinking maybe oxygen sensor . but want to see codes before tring to buy stuff i may not need.. manual says i need dealer mode selector tool . but must be a way to do it without it?
The plug where the manual asks you to use the dealer tool, use a paper clip to bridge across the pins, it is a bad suggestion i know but personally i would be careful doing that as not to short anything but it will do the job , the dealers usually have a “rocker on/off” switch that just plugs in that same port.