How do I change the computer

First, you need to be sure it is the Power-train Control Module (PCM) that is the problem. While the PCM's do fail it's rare. You will need to test each circuit going to the PCM connector's before you can be sure it has failed and you must test all these same circuit's before installing a used or rebuilt PCM. If not what ever shorted the original PCM will damage the replacement. You can go to your local library and find a manuel that has the pinout diagram and spec's of your PCM and test each circuit for it's power, ground and resistance. Once they all test out with the key off than the key on test's you will know whether you need the PCM or that you have a problem that is the cause. To remove the PCM behind the glove box you will need to disconnect the Neg battery term. Then disable you Air Bag system, which you will find is called the Safety Restraint System (SRS). Once that is done you need to ground your body the the frame of the car to discharge any static elect. in your body to keep from damaging your old and new PCM. Once removed you will have access to the three PCM connector's that you will need to test with the battery hooked back up, they are pinout Red A-B, White C-D & Blue E-F. Normally A thru F there are 16 pins each = 96 pins. Some will be missing only because it was not needed on your model. Follow the testing guide line's and should you just happen to have a failed PCM you should be just fine. Older model's don't need programmed but warning. You do have a Passlock Ignition lock out system and should you not follow the auto programming guide you will need a shop or skilled locksmith to re-enter the Passlock codes into the BCM & PCM to restart the car. Good Luck