In the 2 months I've owned my Miata, I have tried everything in the world to stop this annoying metallic vibration under heavy engine load. From what I could tell, the sound was coming from near the gauge cluster/under the steering wheel. I've removed the lower dash at least 10 times to zip tie, shove paper towel between places, etc. But to no avail. Fast forward to tonight...
I replaced the motor mounts. Install went fairly well, with a few unexpected twists and thoughts of giving up along the way, as any good automotive project goes
I realized the driver's side mount would be easier to remove with the air intake box out of the way. While removing it, I noticed that a small bolt that holds the air box to the body was missing. Sure enough, rocking the box back and forth made that same metallic vibration sound I've been trying to get rid of. When I put everything back together, I shoved an oil rag where the air box meets the body and, PROBLEM SOLVED! So now I have new motor mounts, better feeling shifts, and one more silly rattle gone from my life. Did I mention it's the weekend?
I replaced the motor mounts. Install went fairly well, with a few unexpected twists and thoughts of giving up along the way, as any good automotive project goes
