 reset codes
The reason your check engine light is on may be because the code is stored in memory. You need to tell the computer to reset the check engine light, this will turn the light off until the computer senses another failure event. You can reset your check engine light a number of ways: 1. Buy a carchip, you can get the carchip at sears or other places, they are about $100, it fits in the com port below the steering column. You can leave the carchip plugged in while you drive, and when the check engine light comes on, you remove the chip and connect it to your home computer. The carchip will let you know what code(s) are the problem. This definately helps in diagnostics and can prevent you from buying parts you dont need. When you connect it to your computer you can "clear" the check engine light, thus, when you plug it in to you expo, the light will go out. 2. method number 2 is cheaper. disconnect the battery. | 
