I have an original MBP that did something like that... I put 2 stickey notes on the battery (spacing or insulation-not sure which) and reinstalled the battery. Works just fine now. Of course, mine is way out of warranty.

Unfortunately, your issue appears to be hardware-related, not software. I would call AppleCare and setup a mail-in repair - you will save yourself a long drive (or two), and the Apple Store is probably going to send it to the depot instead of attempting an in-store repair.

I just sent in a display, it was turned around the same day - the depots appear to be pretty efficient currently...

The unibody models are constructed from the top case down, making the trackpad and keyboard the hardest parts to get to - complete opposite of the PowerBooks and earlier MacBook Pros.

You'd need to take the bottom case off. First inspect the battery to see if its swollen at all. If not, there should be a tri-wing screw on the underside of the trackpad. Adjusting this can affect the click, you'll have to experiment a bit. And you'll need a tri-wing screwdriver obviously.

check here:

http://discussions.apple.com/thread.jspa...

I think that trackpad problems like this come with use of a laptop. The best fix would be checking the components under the click, the mechanism that registers your click. Apple might do this

My trackpad scrolls fine, and does all the gestures but is not clicking what is the problem? any advice?