http://www.free-lemon-law-guide.com/the ... ss-act.php
For every mod you do, that guide is your bible. For instance, I have an intake and cat back exhaust. My exhaust is no longer covered under warranty for any defects. Greddy would have to cover it. However, the catalytic converter and emissions portion is still covered under warranty because I haven't modified it.
My intake is now covered by Injen, but if my power steering fails, Nissan must still cover that because they cannot prove that the intake was the sole reason for the failure. However, if one of my cylinders shoots out of my engine (highly unlikely because all an intake seems to do is add noise and look good), they may be able to make an argument that the intake caused too high a compression and not cover the engine. Again, highly unlikely. You need to do some serious modifications like forced induction or boring and changing cam shafts before you really need to start worrying about what your warranty will cover/not cover.
Read your new bible and you should be okay.
