Originally Posted by CaptMoto

If no one's interfered with the fuelling this doesn't go crazy by itself from one minute to the next. So let's not panick, first port of call is to inspect / clean / change the spark plug, as it can have residues in there due to long inactivity.

After this, since Badga has both DNA filters stage 1 & 2 I would give them a good ol' cleaning and spray them with the reactivating polymer oil spray.

lastly I would check and spray the tickover screw to ensure its not worked itself loose and that its not got salt debris preventing it to operate smoothly.

The fuelling fix would be the last thing I would try. It's an elelctronic setup achieved in the diag mode and it doesn't forget its setting unless like I said someone had "fiddled" with it.