I just fixed an underhood buzzing (rattling) noise today on the '07 Fit and I thought I would tell everyone what it was.



The noise occurs during high idle (when the engine is cold), and holding the heat shield on the rear of the engine (#4) stops it:



Tightening the three mounting bolts #9 had no effect. The problem is that what looks like washers on the shield, in the picture, are actually metal grommets. They have a steel-wool like substance that is supposed to hold the grommet tight to the heat shield. On our car, the bottom grommet was loose, so even when the mounting bolt was tight, the shield rattled.


My fix was to "re-pack" the steel wool into the grommet to hold it tight. I just jammed a screwdriver into the wool to accomplish this.

For good measure, I packed some high-temp RTV gasket maker in there.

Just thought I would share...


PS: For you kids at home, don't touch the heat shield unless you are wearing heavy insulating gloves! Don't ask me why I mention this....