2004 v6 Mustang engine rattle

I have a 2004 v6 automatic mustang with 125k miles. Around 105k miles my car started randomly making a rattle from what sounds like the engine when I accelerated and it’s been slowly getting worse. Now it is a loud rattle that only occurs in third gear or higher and only in certain parts of the throttle. The rattle sounds like a metal on metal rattle and it only happens between 2000-3500 rpms and it does not happen is first or second gear or at idle, so I cannot listen while revving it. Also, it is the loudest when I am going up hill and automatically stops when I let off the throttle or accelerate harder. My car has a p1336 code which is labeled as a misfire monitor hardware code and a reported fix is the camshaft position sensor and sycroniser assembly. I replaced both but it did not fix the nose. I also turned the crank and it seemed like the timing chain was not stretched but I am not absolutely certain that it’s not bad. This link is to a video of the sound happening, you may have to turn up your volume to listen but it is much louder in person. https://youtu.be/b5B-k5Ot1oY Anyone who has an idea of what it could be please let me know. Thanks.

I did hear the sound on the video… are there any vibrations that go along with this rattle sound? It could be an unbalanced wheel/tire vibrating just about anything in the vehicle. So need to know if there are vibes that go along with this noise.

It can be a heat shield, but doesnt sound like one…unless you can get this noise to occur when stationary…if you can, it can be a heat shield. If you cannot, it is another component, unfortunately it can be any component that is free to vibrate and make noise.

It can also be a Misfire that you are hearing…again, vibrations would occur with this and power delivery would be affected.

But my gut feeling is with an unbalanced wheel and tire which is vibrating something else, only you could tell us if it is this because you would FEEL it and hear it… It can also be something in the trunk like the springs under the rear decklid for the trunk.

Your options, unfortunately are anything that can rattle or vibrate so you are the most likely one to solve this, not us. Good luck and dont go driving on the highway with sounds and CEL’s illuminated…its usually not a good thing.