Check engine lights can be a real problem. You see the thing with the check engine like number one; you have to understand what it’s telling you. The yellow check engine light means you have an emissions control problem on your vehicle. Do you have to stop right now? Now you don’t have to stop right now, but you have to prepare that you need to get your car checked. Now what does checking for the check engine light actually entail? Well somebody, either you or a technician is going to connection some type of test device into the diagnostic link under the dash of the car. Now that might be something basic, like a simple code reader. Or it could be something really complex and exotic like this unit (pictured below) from Snap On tools.

Now, whatever you use, one of the things that is going to come up is a code. Because when the check engine light comes on it sets a numeric code in the computer and that numeric code tells you what is being affected by what’s wrong with the car. But you’ve got to remember that the code doesn’t tell you what is actually wrong.

So how do you find out what’s wrong? Well what you do is you refer to a service manual or some type of information service. And it will tell you what you do to check to see the cause of the check engine light. This particular code refers to a crankshaft position sensor but if you walk down through the test procedure you will find that there are numbers of different things that could cause that code other than the sensor itself. So always make sure that the technician uses something like this to check to see exactly what’s wrong. Otherwise you may end up in the world of oxygen sensors. One of the most over sold parts on the planet. Why? Because there are a hundred different things that can cause an oxygen sensor code that have absolutely nothing to do with the oxygen sensor and far too many people never run the diagnostic. So check engine light, code, run the test procedure that matches the code, and you will save a lot of money.

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