For at least seven years my old Ford Focus used to flag up "engine malfunction" and put itself into limp mode. All I had to do was pull over, stop the engine for ten seconds and start up. Problem solved. It might do it twice a day, twice a week or twice every six months. You would never know. Issue never resolved and there were no error codes. Blind panic the very first time it happened, breakdown callout, the lot, and shoulder shrugs after that.