This is from: http://www.dmv.org/automotive-law/lemon-law.php
If you think you might have a problem, you can start here to get an idea on your states' Lemon Law.
A Lemon Defined:
The state defines a "lemon car" as a new vehicle that has a single problem (or series of problems) that is covered by warranty that seriously impairs the vehicle's use, value, or safety.
If your new vehicle is less than a year old or has less than 18,000 miles on it, and is either a passenger car, light truck (weighs less than one ton, and is not used in business), or a motorcycle, it's covered.
Fixing the Problems:
If your vehicle has a problem, take it to the dealer or manufacturer and asked to have it fixed. They need to be given a "reasonable opportunity" to do so.
What is considered to be reasonable? If at least one of the following is true, then you've done your part:
At least three attempts have been made to repair one problem, and yet the problem continues or occurs again.
The vehicle has been in the repair shop for a total of at least 30 days in its first year or within 18,000 miles.
At least eight attempts have been made to fix different problems.
At least one unsuccessful attempt has been made to fix a problem that could cause death or serious injury.
(An example of the latter would be a brake problem that can't be rectified.)
If you signed an agreement when you purchased you car to have disputes settled by way of binding arbitration, Lemon Law can still help get you to binding arbitration.