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What Does This Check Engine Light Really Mean!?

Published Aug 28th 2007, 6:39pm by Jody DeVere in Featured Articles

Checkenginelight by Kim Walker
One of the most hated phrases by our customers is the dreaded "check engine light" (CEL).  It causes such pain and uncertainty.  The check engine light may come on if anything, yes - anything, is not working 100% under the hood of your car.  Can you imagine just how numerous the actions are that take place under the hood of your car?

    * Shouldn't this light be caused by one thing going wrong?
    * Was the CEL created by the vehicle manufacturer as a conspiracy to get you in the shop?
    * Wasn't I just in the shop for a CEL two weeks ago?!  How can this be!
    * The light pops on at the most inconvenient times, doesn't it?  Sometimes, it comes on and stays on, other times, it comes on and blinks, yet other times, it just pops up intermittently.
    *  That light is also usually a bright orange or red which really frightens some drivers into calling immediately from their cell phones while driving.
    * While, some clients don't see the blinking red and orange as important but simply a nuisance and instead of calling right away - they wait a few days, weeks, or yes, even months. 

Please, allow me to shed some light on the mysterious CEL.

Your CEL may come on and stay on, come on and blink repeatedly, or it may come on and off intermittently.  Each may have different meanings and/or causes.  What is important to know is that when your CEL comes on, bring it in to have it diagnosed.  There are hundreds of causes for the CEL and the only way to know what is triggering the light is to have it diagnosed.  Many times, clients come in with the CEL on and have been driving with it on for a while.  Some have covered it with black tape, pictures of their children or something else just so they don't have to see the orange monster. Doing this will only allow the problem to continue and potentially make it worse and/or multiply.  Then at the time that you bring it in you may have multiple causes for the CEL.

Here are some common causes of the CEL:

    * O2 Sensor(s)
    * Catalytic Converter failing
    * Ignition Coils
    * Ignition Coil Module
    * Coolant Temperature
    * Mass Air Flow Meter
    * Air Temperature Sensor
    * Computer
    * Spark Plugs
    * Spark Plug Wires
    * Gas Cap Leak
    * Vacuum Leak
    * Bad Gas
    * many, many more!

Woman_with_engine To diagnose your CEL, it is helpful for the technician to know details about what was happening with your car when the CEL came on.  Were there any odd noises, smells, smoking, etc?  How fast were you driving? Was the car hot or cold?  Was it in the morning or the afternoon? Siting at a red light or in a carpool lane?  Did you just fill up with gas?  Pay close attention if/when your CEL comes on and be prepared to tell your Service Advisor as much as you can to help the technician duplicate the concern.  Do not be surprised by diagnostic fees when you drop your vehicle off.  Automotive repair shops must charge a diagnostic fee because of the amount of time invovled in diagnosing a problem, the experience of the highly paid, highly trained technician who is performing the diagnosis, as well as the very expensive diagnostic tools that are required.  One of our tools costs nearly $12,000, so you can see why charging a diagnostic fee is not only senseworthy, but also a necessity.  In order for technicians to connect to your vehicle's OBD (on board diagnostics) we must have the appropriate tools and equipment to be able to do that.  Therefore, at Peak Automotive we do charge a diagnostic fee.

If you are looking for more information, I like THIS ARTICLE about the CEL because it explains fairly well some of the common questions relating to the CEL.

If you ever have any questions regarding your vehicle's Check Engine Light (CEL) do not hesitate to give us a call!  Your Service Advisors, Michael and John, are always ready to answer your questions!  Give them a call today at 919-363-7077.

Kimwalker_small by Kim Walker of Peak Automotive

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