Check Engine Lights

The check engine (also known as “service engine soon”) light is one of the most misunderstood indicator lights on your dashboard. This is because most of the time when the light comes on the vehicle seems to be running just fine. It feels like a false alarm. Chances are good that the underlying problem is something simple and easy to fix. Then again, it could mean big bucks. You just never know. That's why it's so scary.

If you have had this problem with your vehicle, you are not alone. We get phone calls every day regarding the dreaded check engine light. Our standard answer is: "If there are no drivability problems then you can keep driving it and bring it in at your earliest convenience for us to diagnose. But, if the check engine light starts flashing or your vehicle is having any drivability problems (hard to start, stalling, slow to accelerate, black smoke coming out the back, etc.) you should Tow it to the shop ASAP. If you continue driving when the light is flashing or the vehicle is having drivability issues, you can do damage which could require an expensive repair. The longer you drive, the more expensive it becomes."

If that light comes on and your vehicle is not driving any differently than normal, you need to understand that your car is working overtime to do this for you. The ECM (Electronic Control Module) or computer that controls the engine operation is constantly monitoring and adjusting dozens of components, various sensors and other electronic devices to provide you a smooth ride. So even though everything seems to be working, when the computer senses that there is a problem it turns on that blasted light to tell you that there is a problem, and stores a code(s) in the computer's memory. Your job is to get your car into the shop, and get a thorough diagnosis.

Once your vehicle is in the shop, our technician will scan the computer to get a reading on what the computer is seeing wrong, and to get a reading in which direction we should start looking to find the problem. The scanning tool gives the technician a trouble-code(s) to look up in special service manuals. Unfortunately there are hundreds of different codes. We get calls to the shop all the time wanting to know, "Do you have one of those computers that hook up to your car when the check engine light comes on and tells you what is wrong with it?" Now this is the important part to understand: The computer doesn't just tell you what is wrong with the car and the code itself doesn't always tell exactly what component is defective. Sometimes it only tells what engine parameter is out of normal range. If this happens the technician will have to perform further testing to pinpoint the defective part. To make this even harder to understand, sometimes it can cost more to diagnose the problem then it is to replace the part that fixes it. This boils down to: It's not always an easy fix!

Granted, sometimes it's nothing more than the gas cap not being fully tightened after filling the tank. Or, it could be a tank of bad gas. A word of advice: never fill your tank while the engine is running.

But remember, there could be hundreds of different reasons why that pesky light comes on. It is very common that a check engine light will lead to a sensor that needs replacing. This being said, after having one sensor replaced it is not uncommon for that darn light to come back on again. It can be very frustrating for the customer and uncomfortable for us. It's very common to have more than one fail at the same time, and we may have to do further diagnosis because the first bad sensor was masking a problem with another system. Most technicians hate complicated engine problems, but not us. We have four ASE Master Technicians on staff, waiting to assist .

If your check-engine light comes on, here are tips on what you should do:

Look for a serious problem that requires immediate attention.Check your dashboard gauges and lights for indications of low oil pressure or overheating. These conditions mean you should pull over and shut off the engine as soon as you can find a safe place to do so. If your gauges read normal take your vehicle to the shop as soon as is convenient.
Blinking Lights mean "Stop Now!"If the "check engine" light is blinking or you notice any drivability problems, pull over and shut off the engine! Tow your car into a shop as soon as possible to prevent expensive damage.

The Check Engine Light is really your friend. It is working hard monitoring your car's engine and making adjustments. So you can jump in your car and rush off to where ever you need to be without a thought to your car's performance. So, if that light comes on to tell you there is a problem, don't ignore it. And please don't get angry with your Technician if they can't tell you exactly what is wrong right away. Cars are incredibly complicated and getting more so each year.