Hy everybody, just an update on my Cavvy, turns out the bubbling noise is either a cylinder head gasket needing to be replaced, or a crack in the cylnder head. I think if it turns out that there is a crack in the cylinder head, it might be the end of the Cavalier. The little 2.2l do have over 200K on it, so I doubt it can take much more. We'll see.