INFORMATION FOR CONSUMERS WITH
“CHECK ENGINE LIGHT” PROBLEMS

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If you own or lease a vehicle with repeated “check engine light“ problems, the Law Offices of Delsack & Associates, P.C. may be able to help you get rid of your vehicle and recover all, or most, of your money.

History and Background
What the "Check Engine" Light means
What to do when the check engine light turns on

Check Engine Light: (top)
HISTORY AND BACKGROUND

For decades, cars had dashboard indicators that only monitored the basics: fuel level, oil temperature, coolant temperature and whether the generator or alternator was charging. That all changed in 1981 when federal clean air statutes required catalytic converters to be put on all domestic cars and light trucks to help reduce the level of smog-causing emissions in the atmosphere. Emission control is a process that involves sophisticated sensors that compare the air contents entering and leaving the catalytic converter. Because so many other parts of the engine affect what ultimately comes out of the exhaust, it takes an on board diagnostic (OBD) system to keep everything performing properly.

In 1996, the federal government required U.S. automakers to upgrade to OBD II, a sophisticated system of sensors and actuators that conduct on-the-road diagnostic tests. When the OBD II detects a problem, it logs it as a fault code in the vehicle’s computer memory, and when retrieved via a diagnostic reader this code directs the repair technician to the source of the trouble. Some problems may be major and some not, but because each can affect engine life efficiency and performance, the consumer should investigate them all. The Environmental Protection Agency estimates that more than 6 million Americans are currently driving cars with the “check engine light” on.

Check Engine Light: (top)
WHAT THE “CHECK ENGINE LIGHT” MEANS

Exactly what the OBD system looks for depends on the make, model and year. While OBD II set the standard for American-built passenger vehicles, many foreign automakers have added their own proprietary diagnostics. As a result, the “check engine” lights themselves, and more than 100 possible problems they can detect, vary considerably. Under OBD II regulations, the computer system essentially acts like a built-in emissions testing station which monitors and adjusts dozens of components and processes. It continually samples exhaust emissions as they come out of the engine and when they leave the catalytic converter, the device that removes carbon monoxide and hydrocarbon pollutants from the exhaust. The system also monitors the car's fuel system to ensure that gasoline vapors are not escaping into the atmosphere through a leak or a loose or missing gas cap.

Most problems are caused by air/fuel mixture, bad spark plugs or plug wires, or a failed oxygen sensor. Anything that causes poor engine performance or inefficiency, however, could trigger the light, and seemingly unrelated problems with the transmission, anti-lock braking system or even a loose gas cap could also trigger a “check engine light” warning. Though the warning may be caused by something minor, it can also predict a potentially dangerous situation. A thorough engine analysis by an authorized dealer or mechanic is the only safe and reliable way to find out for sure.

On some cars, the “check engine light” may simply go on; on others, it may flash to indicate an immediate, potentially damaging situation. The light may be turned off either by a repair technician, or the OBD II will automatically turn it off when it fails to detect the problem after several diagnostic cycles. You should read your Owner’s Manual to learn what the “check engine” light means on your vehicle.

Fault codes are numeric codes generated by the OBD II system when a problem is detected. When a sensor registers that is beyond the manufacturer’s normal specifications, or an electronic component has failed to respond to a command from the computer, the computer recognizes it as a fault and records a number that identifies that problem. When it finds a problem the computer turns on the warning indicator which may be labeled "check engine," "service engine soon" or "check powertrain," or simply show a picture of an engine, known as the International Check Engine Symbol.

Check Engine Light: (top)
WHAT TO DO WHEN THE “CHECK ENGINE LIGHT” TURNS ON

When the "check engine" light illuminates, it will either blink or remain constant. A blinking light usually indicates a problem that needs immediate attention such as an engine misfire which may be due to unburned fuel passing into the exhaust system, where it can quickly damage the catalytic converter and require an expensive repair. If that happens, you should reduce power and have the car or truck looked at as soon as possible. In some extreme cases, the car's computer may reduce power, as it tries to limit the risk of damage.

The technician retrieves the fault code and refers to a diagnostic chart or "fault tree" to isolate the failed component. Usually this process results in a swift resolution, although intermittent fault codes may require repeated repair attempts.

Here are some tips on what to do if the “check engine light” comes on. Remember, the “check engine light” can mean anything from a loose gas cap to a seriously misfiring engine. Ignore the warning, and you could end up damaging expensive components. It also can be a sign that your car is getting poor fuel economy and emitting higher levels of pollutants. You should always have the car checked as soon as possible to prevent expensive damage.

1. First, 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.

2. Reduce speed and load. If the "check engine" light is blinking or you notice any serious performance problems such as a loss of power, reduce your speed and perhaps try to reduce the load on the engine, such as to stop towing a trailer.

3. If you have a 1997 or later General Motors vehicle equipped with OnStar and an active OnStar subscription, contact an advisor who can read the trouble code remotely and advise you what to do.

If you have a repeated “check engine” light problem and the problem is still not repaired, the Law Offices of Delsack & Associates, P.C. may be able to help you to obtain a “lemon law” repurchase, and reimbursement of all of your money to which you may be entitled under the California “lemon laws.” Please call our offices at 888-EX-LEMON (888-395-3666) for a free consultation and to learn whether your vehicle qualifies. Or, you may prefer to take a moment to complete and forward to us our submittal form. [LINK TO SUBMITTAL FORM].

To learn more about the California lemon laws or obtain other useful automotive information, please go to our Home page. [LINK TO HOME PAGE].