That'll be the RNF especially if the "Little Tykes" is using Bosch management
OK, lets be serious for 5 seconds regarding RNF
FWIW most Mfrs use RNF these days, that's how (on a decent Diag Machine you get "historic" codes), which of course certain Machines don't show ..................
The fault has disappeared after a few Drive Cycles, so the ECU, (if it's one that is capable) will then file the Code in the Historic Codes.
Mercedes and others call this the "Event Log", and Star Diagnostic, (SDS), shows a little (f) for a historic / intermittent , a big (F) for current code, and for a really old or certain other stuff (f) becomes (i) for Info, which is still found in the Event Log.
This is how a mfr knows if you've been playing with a cheap / lesser Diag Machine, because although you might have cleared a present Code, it will still be stored in the Event Log, along with over revved etc etc, (all Make dependent of course)
My Snap On never used to show Historics, which is why I went for all the Dealer Level Kit, but I notice since Snap On update in Jan that it now does show some Historics on some models
Still what the fuck do I know, I know fuck all