So, my mechanic have concluded that I have a blown cylinder 2. He put Marvel Mystery Oil and I can't really tell the difference. Is there another way to fix the cylinder without having to rebuild or change the motor? It's for a 2011 nissan sentra.
So, my mechanic have concluded that I have a blown cylinder 2.
What exactly does "blown" mean, what is the specific problem with that cylinder?
He put Marvel Mystery Oil and I can't really tell the difference.
There wouldn't be. You can't fix a mechanical problem with snake oil.
Is there another way to fix the cylinder without having to rebuild or change the motor?
Of course not. However the feasibility of repair is dependent on what the actual problem is. For example if you have a burned valve or a head gasket leaking in that cylinder you could elect to repair that. But if you have worn rings, scored cylinder walls, or other serious internal problems it is time for a new engine - or a new car.
concluded that I have a blown cylinder 2
What are the symptoms with the car/engine?
depends what "blown" means. Failed head gasket? Broken piston rings? Just worn out?