mine does it as with a few other 3g's here in phx too

 

never noticed mine doing somethign liek that :dunno:

 

If you take it off, and turn it over, you'll see two little prong / tab things sticking out sideways. With a vise or pliers, very very gently push each of them in a little bit. Use a towel or somethign to keep from scuffing up the top of the cap.

The gasket seals from the top, and the tabs keep the gasket pushed against the valve cover. If you push the tabs in a little bit, you get a little bit tighter of a seal.

It's really easy once you see it...

 

that valve cover gets uber hot and the rubber seal hardens very quickly. I stopped replacing it after the 4th seal. It never helped. I wonder if we could find a seal of a different rubber. Maybe something a little softer or even silicone?

 

my stock oil cap on my 04' GTS spilt a little here and there like u said. I simply bought the oil cap by Injen. Fixed the problem and looks good too! :twothumb:

 

how much? and is it chrome and red?