my 98 crv AT has a rattle at varying rpm and is intermittent. Sounds just like when gravel gets between an exhaust sheild and pipe but I tried a rubber mallet all over underneath and under the hood and can't find it. one time when it was present at idle I got out and it went away...until I got back in, then it strted up every time I lifted my feet off the floor it would stp.
Another time when it was present I opened the hood and it would go away when I pressed down hard on the cam cover on the belt end...any ideas? Motor mounts? Thanks.

 

does it ,the chatter speed up with your speeding up (giving it gas)jus wondering good luck

 

yes, with engine speed but it's present in a very narrow rpm range and not always the same range. Sometimes there when not moveing.

 

check your catalitic
shroud, may be loose.

 

Also check all exhaust hangers.

 

does it get worse in the rain or after driving through a puddle ???

 

no rocks or cracks in shroud and hangers are good. Rain doesnt matter.
Sometimes it will go away if I take my feet off the floor and return when I put them back. Sometimes touching the belt end of the cam cover or the AC compressor makes it go away.

 

Very strange.

 

Just fixed the problem. Replaced all 5 engine/trans mounts. The one on the front left was broken and the others were slightly cracked. $129 on ebay.

 

Thanks for letting us know