Hi try switching the ignition on and off 4 or 5 times before you do much investigating mine went off yesterday for first time in about 6 months after half a dozen restarts it cleared. Don't think I have an underlying engine problem just a touch of stiloitus. It also has a few other hiccups that ignoring seems to cure.
Hope that helps but it's not really good advice just stilo experience over 5 years
only real way is plugging in a code reading device.
some things are "adaptive" so will clear after a few clean starts as you suggest - however I'd rather know what it THINKS is wrong.. before I hit bigger issues,