"'Curly Q. Links'" > wrote in message
...
> " wrote:
> >
> > I have a engine ping or knocking sound (kind of like a gurgling
> > metalic) sound from my engine
> > that seems to occur at specific rpm ranges. It has happened on and off,
> > mostly in the summer. The car has 180K, I take it to a trusted mechanic
> > and do all of the 15,000 mile maintenance work recommended by honda,
> > including oil changes every 6k.
> > Before taking it to the mechanic, is there anything cheap I can try?
> > Thanks
>
> -------------------------------
>
> Easiest thing to check is the coolant. If the reservoir looks empty,
> fill the reservoir to MAX (with engine cold) and see if it is lower the
> next time the engine is cold. As the cooling system expels air it uses
> coolant from the reservoir to replace the air. If you fill to max three
> days in a row it should stop 'using' and you may see your ping goes
> away. The computer can't set timing and mixture properly when the
> coolant sensors are surrounded by air. That can cause ping. No tap water
> BTW.
>
The manual recommends Honda Genuine Coolant, which came pre-mixed the last
time I bought some. If you do your research you should be able to come up
with an aftermarket product that is compatible, but I haven't bothered.
There are products and mixes that can damage aluminum blocks and heads. If
you do find a suitable product that mixes with water, please use distilled
or purified water only.

By the way, my Civic came new, in 1999, with green coolant in it. The
replacement stuff from the Honda dealer is blue. Comments?

Earle