Troubleshooting

Hello, just come back from the first “exit”. Unfortunately not as desired. After about 25km of symptoms as if the fuel would run out, no gas is accepted and rolled out. Afterwards tries to start again and the feeling as if it only runs on a ylinder. I took out the spark plugs, actually didn’t see anything, but since the rear was a bit rough black I changed them for a new one. After that she ran again “normal”, but already after 1 km similar problems. Ic h made it home, but she runs “as she wants”, is that in my opinion the spray ride comes relatively unregulated. So I would actually tap on the Vegaser, but this only runs on a cylinder (feeling) doesn’t really fit there. Does someone have a tip or a guess before I screw on it truelessly? Thank you very much.