I had been noticing an obvious clicking sound under the hood, above the front left wheel area on our 2001 Ody. Thinking there was a problem, when I went to the dealer they all knew about this and said it was normal. Apparently it is a part in the emission control system, and some people can even hear the clicking inside the van. The dealer said it is a problem if the clicking ever stops.
Just wanted to post this in case anyone else hears clicking in their Ody.
2001 EX-NAVI, SS
1997 Accord EX-L, Forest Green
1992 Accord EX, White
1982 Accord DX, Silver