Rattling when idling (!)

I have a 96 Accord LX (auto) with 51k miles. Lately I've been hearing a rattling noise when the car stops or when it's idling. The rattling stops as soon as I accelerate. Any ideas, suggestions are hugely welcome.

Follow Up:

I tested the underside and sure enough I saw the heat shield for the Cat had rusted is quite loose. That's the part which is making the rattling noise.

Anyone knows a good way to clamp it? DO I need a new heatshield?

I had that fixed on my car last year and i didn't realize how easy it is to do. I dont think you'll need a new heat shield, i think it's just regular bolts, get the appropriate wrench, get down there, and you should be able to see how easy it is. Just tighten the bolts and the rattle goes away.

Why would it stop rattling upon acceleration though? Does the sound continue at higher RPMs in neutral?

tighten up the heatshield, it's such a common problem in especially 5th gen accords its disguisting. But anyhow, get a new one, or remove the old one completely (just don't park on high grass because it may catch fire from the heat).

- Nathan

tighten up the heatshield, it's such a common problem in especially 5th gen accords its disguisting. But anyhow, get a new one, or remove the old one completely (just don't park on high grass because it may catch fire from the heat).

- Nathan

The common problem I have always read about (and experienced) was a rattle/vibration noise that was heard around 1700 RPM. I have never heard of anyone experiencing the "heat shield" issue at idle, but not anywhere else on the tach.

Thanks everyone.

The rattle is lour and clear around 1000 rpm (idling in neutral, park or gear)
There is also a rattle (which I failed to listen to earlier) when I start to accelerate and the tach shows an RPM of about 1400rpm. There is no rattle at higher RPMs.
Anyway I am going to do it in a couple of days when the weather is supposed to be nice(I live in the NH tundra)

By your new description, I'd agree -- it's the heat shield.

well, with my own personal experience, i had a catylitic converter go bad.... i guess the ceramic stuff in it had shattered adn was rattling. It made sound more like something was loose and being blown around(obviously it was). On the contrary, my brothers 93 accord coupe had the typical heat sheild noise but it was more like a vibration... thas prolly the prob you have but if not, hte cat is a shot...