Intake leak

I'm not for sure if I have a gasket problem yet, but I think I do and I was curious whether it usually the Lower or upper intake gasket that fails, or are both a problem?

its the lower, but you need the lower and upper gaskets aswell as valve cover gaskets when doing the fix, as well as other goodies too

Might check this out for some info on the problem:

http://forum.freeadvice.com/archive/index.php/t-194703.html

And some replacement advice:

http://www.denlorstools.com/index.asp?PageAction=Custom&ID=27

what can I do to check it without taking it to a shop