You need the correct software and lead to get the codes. There prone for backfires there a pita. I had one last week, the cam sensor wires were broken at the plug. They looked good but came off with a firm pull. All 3 were broken. Also check the plug gap, too much gap causes backfiring but shouldn't put the eml light on.
This is ONLY to be used to report flooding, spam, advertising and problematic (harassing, abusive or crude) posts.