Q: Engine noise when I press gas pedal

You most likely have a warped exhaust manifold that has caused one of the studs holding the manifold to the cylinder head to break. When this happens you will get a loud exhaust leak that can be quite annoying. I have done many of these myself. It requires some special tools and techniques to make this repair. If not done correctly the cylinder head may be damaged. I would have a qualified mechanic replace your exhaust manifold. That way you can avoid any extra expenses from having to remove the cylinder head.