The oil levels are ok, but i'm unsure when the last service of the car was. I took the car to kwik fit and they said that there was a bolt missing from the manifold cover, which could be causing the rattling...I dont know much about cars but i don't think it is this as the longer i drive the louder the rattling becomes. they also said that the engine fan always coming on could be becuase of a faulty sensor....when i first start the car and drive thats when the car seems to pull back when i rev as if theres no power, its really winding me up!!