1999 Mountaineer - strange rattle

[Zuiun]

I have a '99 Mountaineer (Monterey package, V8 engine, AWD) with approximately 113,000 miles on it. I've had the vehicle since 60,000 miles and so far it hasn't required anything but routine maintenance (oil changes, etc.).

Recently, it's started exhibiting a strange, metallic rattle when I come to a stop. It sounds like sticking a pencil against the blades of a metal fan.

It doesn't do this all the time. And when it does, it will just rattle for maybe a second and then stop. Maybe do it once or twice when stopped. So far as I can tell, it's never made the noise when the vehicle is in motion (but it hasn't been that long since it started).

I plan to take it in to have it looked at, but since it's not consistently reproducible, I thought I'd toss it to you guys to maybe get an idea of what I can ask my mechanic to look at.

[shorod]

Your description sounds pretty similar to how a loose catalytic converter heatshield may be described. When a weld or two break, often the converter shield will rattle at idle or just off idle. You may try shifting to neutral or park with and slowly depress the throttle to see if you can get the noise to recreate itself long enough for someone to identify where it's coming from.

If it's a heat shield you could replace the converter, try to have it rewelded, or just install one or two large worm-drive hoseclamps. Such clamps can often be found in hardware stores in with the furnace duct work.

-Rod