Hi. Without a picture, this is going to be a "huh?" post but let me try anyway ( I will snap pic of no one can figure this out). If you look straight over, down and behind the 2.2L Ecotec engine (let's say with a flashlight) you will see a cylinder-shaped component down among the suspension components. But based on the location, it is not a suspension component, not near the wheels or anything. It is straight back, behind, and down below the Ecotech engine. I was giving the engine compartment a look over and noticed that the cylinder has a joint in the middle and the joint is open about 1/4" or so. I thought that is strange, it looks like it should be entirely closed, whatever it is. I stuck a wire hanger down there, behind the engine and there is definitely an opening in the cylinder on the top of it. Whatever it is, I don't think it should be open down there near the ground. But don't know what it is. Not part of exhaust system as far as I can tell, nor suspension. Does anyone have any idea? If not, I will come back with picture. Cannot understand why it has an open joint on top. Thanks, Dauntless.