If it re-appears, immediatly put the old coil back in. There's always the wild card issue of
oil-filled coils being mounted sideways, so you get an increased mark on a response if you include it.
I bet you just clogged up the bleeds a little bit with that goofy two-step you did with your fuel pumps last week. A blast of carb cleaner down all of the bleeds will probably make it go away.