check engine light

Hi Guys, first post here so please be gentle 😂 I bought a 128 GT a month ago and have been ragging it about. However, today on my drive home from work, about 50 minutes in, I stopped in some traffic when the engine light flashed for about 5 seconds and then went off. Does anyone know the cause...

Got a bit of a strange intermittent issue. Day to day car runs fine, starts fine, doesnt idle high, revs fine and pulls fine. Then at motorway speeds it'll randomly loose power, slow to 50mph and sound like its either misfiring or being limited to 50mph. Similar sound to a pit limiter on a race...