I don't have any knocking/pinging in my 2003 Accord V6, but if I did
here's what I'd do: Next time you get gas, fill it with premium. If
the knock is no longer there when climbing the grade you will know that
the engine management module/knock sensor that controls the timing is
not working properly and needs to be replaced. Your car and mine should
not knock when using regular gas. As far as getting the dealer to do
something, you will probably have to be more agressive and go up the
Honda ladder past your local dealer's service manager.

Brian Stell wrote:
> Al Franz wrote:
>
>> Wrote a note in the newsgroups a few weeks ago about a pinging noise
>> my Honda Accord V6 2001 was making when the engine was strained, going
>> up a hill. Many gave me good advice and asked to let you know what I
>> find out.
>
>
> I have knocking in my 2005 Accord V6 as well. But only in the 2200 to
> 2800 RPM range when climing a slight grade. Could not reproduce it for
> the dealer (totally flat terrain near them) so have not been able to get
> help from the dealer.
>
> This only is really bad on one short stretch so I just go slow to keep
> the engine at about 2000 RPM (neither I nor the people behind me are
> thrilled).
>
>> The Honda dealer mechanic went out with us and this is what he said.
>> He thought the noise was coming from the Hydraulic Lifters.
>
>
> As already stated: the lifters should be affected by RPM (more RPM =
> more noise) but not by throttle. And noisy lifters make a clicking or
> banging sound, not a pinging / rattling-ballbearings sound.