Solved! Annoying Vibration Sounds from the right rear of my Corsair

[DrMitoFit]

I have a 2021 Corsair Standard with metallic vibration noises coming from the right rear when driving over rippled road surfaces or slamming the right rear door shut. It was coming from TWO different sources, but I fixed both. It looks like I may have deleted my first post while editing (or someone else deleted or moved it), so I am reposting.

Right rear bumper marker light has an internal metal reflector that is loose from the factory, replicate sound by pounding it or the right rear bumper. I am NOT talking about the tailgate mounted tail light. Solved by drilling a 1/4" hole in the black interior face of the marker light housing and dripping some caulk onto the interior of the light housing at the upper curved seam where the reflector makes contact with the housing. Worked great!

Amplifier and its bracket vibrate like a tuning fork behind the right rear quarter panel interior trim. Replicated by slamming the rear rear door shut. The amplifier's wiring harness has a rubber mounting grommet that must have fallen out of its slot at the bottom of the bracket. I removed the amplifier with its bracket and inserted a piece of foam between the amplifier and bracket (eliminating the "tuning fork" resonance) and plugged the wiring harness' rubber grommet back into it's slot at the bottom of the bracket (which also helps deaden vibration).

Now my Lincoln Corsair has a quality sound when shutting the doors and drives without the annoying metalic vibrations for the first time ever!

 

[Oanghusa]

I had the exact same amp rattle. It's gotten worse lately. I never heard it before the last few months. I did the same check as DrMitoFit by removing the side panel trim and examining the amp. I could get it to rattle by poking the amp gently with my fingers when in there, getting the same noise I hear when driving on rippled pavement or even sometimes at idle at a light. I put a piece of foam in between the amp, body, and amp bracket in a couple places but could not stop the rattle. I then loosened the three bracket screws, intending to remove them and pull the amp and bracket out and look at the other side and see if I could figure out a good spot for the piece of foam or tighten the amp mounting screws.

After the 3rd screw was loose, the amp dropped down about 1/4 inch without me touching it, so I stopped to assess before removing the screws. Now when I poked it or did what I had done before to cause a rattle, it was silent! I tightened the screws with it in that new location and it was still silent. No foam needed! The rattle is GONE! Thanks to DrMitoFit for the info and photos that got me looking in the right place.

I don't know why it had gotten worse lately. When I got the car a year ago, it did not rattle. It was rattling before some body work, and I do not think the body shop needed to get into that panel in their work to replace the bumper cover and repair the dented tailgate (small dent below the license plate, roughly oval shaped, from the FORD badge of the Transit 250 that rear ended me at the end of April). Just needed a stone deflector (panel inside the bumper), upper bumper and a bumper light and repair of the dent). But the repair is guaranteed for the life of the car by my insurance and the body shop, so if I hadn't found the rattle source, I would have asked the body shop to look into it.

 

[DrMitoFit]

I had the exact same amp rattle. It's gotten worse lately. I never heard it before the last few months. I did the same check as DrMitoFit by removing the side panel trim and examining the amp. I could get it to rattle by poking the amp gently with my fingers when in there, getting the same noise I hear when driving on rippled pavement or even sometimes at idle at a light. I put a piece of foam in between the amp, body, and amp bracket in a couple places but could not stop the rattle. I then loosened the three bracket screws, intending to remove them and pull the amp and bracket out and look at the other side and see if I could figure out a good spot for the piece of foam or tighten the amp mounting screws.

After the 3rd screw was loose, the amp dropped down about 1/4 inch without me touching it, so I stopped to assess before removing the screws. Now when I poked it or did what I had done before to cause a rattle, it was silent! I tightened the screws with it in that new location and it was still silent. No foam needed! The rattle is GONE! Thanks to DrMitoFit for the info and photos that got me looking in the right place.

I don't know why it had gotten worse lately. When I got the car a year ago, it did not rattle. It was rattling before some body work, and I do not think the body shop needed to get into that panel in their work to replace the bumper cover and repair the dented tailgate (small dent below the license plate, roughly oval shaped, from the FORD badge of the Transit 250 that rear ended me at the end of April). Just needed a stone deflector (panel inside the bumper), upper bumper and a bumper light and repair of the dent). But the repair is guaranteed for the life of the car by my insurance and the body shop, so if I hadn't found the rattle source, I would have asked the body shop to look into it.

The amplifier bracket has hooks at the top mount and the rear mount that allow it to hang in place as you tighten the bolts. Maybe the hooks were not fully engaged. It also helps to plug the wiring harness grommet into the lower oval hole, because it helps dampen the resonance.