At some point the powers that be decided that it would be easier to figure out what was wrong with your car if it just told them what the problem was. Sounds like a great idea, right? In some ways it was, but there are 10,000 different diagnoses your car can give, so putting your finger on the right one can be difficult.
Figuring out how to fix the problem is another kettle of fish, but the first step is to know what your car is trying to tell you. The language it speaks is OBD, which stands for On Board Diagnostics. If something goes wrong, a technician (or you if you have a $59 code reader) can plug into your car, and will get a numeric code telling them what is amiss.
Often your car will let you know ahead of time when something is screwy by turning on the Check Engine Light. Unfortunately there are dozens of stupid and unimportant reasons for the light to come on. But checking the code will give you something to go on whether it's important or not. If your Check Engine light is on, do a quick Check Engine Checkup to be sure it's nothing common and meaningless (which translates to "easy to fix for free.")
Tip: AutoZone will read your codes FREE. All you have to do is ask!
Once you have your code, go to our expansive database to find out what it's pointing to.