The little rubber grommets do fail. (I replaced my 1991 Civic's for the first
time around 150k miles.) They're also known as "spark plug tube seals." They're
item 7 at Majestic's online site, http://tinyurl.com/2tl6l .

Often they're sold in a kit containing the valve cover gasket, the valve cover
screw grommets, and the spark plug tube seals.

Autozone and similar places sells such kits for around $30, but reports around
here are that the material is inferior to OEM.

Probably prudent to buy the kit and replace all cylinder cover seals, unless you
happen to have done the others recently.

My car's valve cover screw grommets failed recently, too.

"civic95" <don1867@nospam.yahoo.com> wrote
> I went to change the plugs on my brothers car and found oil on 3 of the
> plug boots. Is it just a bad valve cover gasket or maybe those little
> rubber grommets, or is it something worse? Thanks.