Other day I had noticed this bizarre sound coming from underhood. Intially, I thought it sounded like a timing chain rattling against a sheet metal housing or something....

OK... staring under there whilst it's running and the noise starts... and I'll be darned if it's not the coil pack bracket.

Dunno how... or why... except maybe just vibration over time... but the two upper lugs where it bolts on just sheared off.... so it's only held on by the lower portions of the mount. At certain RPM it hits it's resonant frequency and voila! The ringing chain sound.

Anyone else ever experience this? I can't imagine what Fomoco would charge for this dealer-only part... so I may have to cruise a salvage yard or two to get one.

Truly inconvenient...

 

Wow, never heard of that occurring. I may have the stock 4.0L coil mount bracket from my '05. Let me look this weekend. PM me if you're still looking for one and I haven't posted back here.

 

Thanks. PM transmitted!