Thank you all for the suggestions! Special thanks to sailor.
I though about the fact that the heat shield is missing but I could not believe that the engine bay temp can be that much hotter without the heat shield so I removed the exhaust manifold and found a small crack. The crack is located on the first pipe on a weld seam.
I'll see tomorrow if I can have it welded or if I have to find a replacement.
I'll update after this part is fixed.
Thanks to you all again.