Hi guys, I have a 2001 600 with some problems. Well, I guess it's one problem. At first it started as a quick engine cut out randomly. The engine would die for half a second and then start up again, leading to some fun experiences on the highway. The red FI lamp would turn on for up to 2 seconds and then go out. I figured it might have been old, ****ty gas in it so I filled it up with new and drove it again. The problems continued and after some time got worse. The engine died like 6 times in a couple of seconds but then ran as usual. At no time it ran bad while function as it should. I had to keep driving since I needed to get the bike home. But it only got worse and in the end I had to stop and start the bike again for it to run. No problems starting it back up, and it ran ok. Except for when it cuts the engine that is.
When I got home I managed to capture it on video when running the engine in my garage and now the rpm isn't stable either.


PS. my neighbour is mowing the lawn in the background, so thats the engine noice at the end.

So, some background and possible issues:
The bike stood for almost 2 years and I was stupid enough to just start it with the old ****ty, swedish gas in it
I installed a speed healer this spring but that just connects to the speedometer, so it shouldn't be an issue? And it shouldn't be getting worse?
I'm not experienced at all when it comes to fixing bikes, so please give me some easy tips on where to start.