I have a mp3 250 2007 model. It was working fine and has been sitting in the garage for last 3 months. Last week I tried to start it. I fully charged the battery and replaced with fresh gasoline. At the first try, it will start but not stay idling unless I open the throttle. Once I let the throttle go, it will shut itself off.
The 2nd try, it will not even start. I have to unplug the key, wait a few minutes, turn it on, it will start but not stay idling. Then 'Check Engine' Light will turn on.
I searched online, someone had similar problem and suggested it could be the air filter blocking the air. So I cleared the air filter. It is sure very dirty and sticky on the surface. I washed it, let it dry and then sprayed K&N air filter oil. It has the same problem even without the air filter in place.
Do you have any suggestion? Thank you.