Less is Better
I pulled the car out for it's first drive of the season the other day. Started it up and noticed a new instrument in the usual chorus of noises that the car makes. A noticeable vibration noise from the back at idle that went away with a stab of the throttle. I went for my drive to get my first driving impressions of my new ShiftR111 and found that the noise would come and go with different engine speeds. When I got home, I tapped on the diffuser and around the rear license plate panel and could tell there was some resonance after the tap. It turned out to be the screws holding the heat shield to the back side of the license plate panel. Something to look for if you're experiencing the same kind of noise.