How To Handle Your Car's Check Engine Light

A blazing yellow light suddenly shines on the dash of your car. Some drivers panic and pull to the side of the road. Others glance with a disdain having seen it a hundred times before. "Engine" or "Check Engine" (sometimes just a picture of an engine) can, after all seem to be an ominous warning of impending doom. Why don't they just show a picture of the engine blowing to pieces or maybe dollar bills flying out of your pockets? Maybe there isn't an international symbol for those.

Or maybe it's just one of those lights that the car makers program to come on so they can soak you for "scheduled maintenance", like changing the winter air for summer air in the tires. Sorry, no conspiracy this time. Not even a good time to panic and over-react. You can blame the Government if it makes you feel better. You see, Uncle Sam just doesn't trust the auto manufacturers to make all mechanical devices on your car run perfectly forever. Silly them! So when one of the hundreds of devices or thousands of computer software lines fails to perform properly to assure a clean running car, pop this light on and cause the owner to lose some sleep.

The Malfunction Indicator Lamp (MIL), or the "Check Engine Light", is commanded by the on-board computer whenever a fault is detected in one of the monitored systems. Most of these systems deal exclusively with control of emissions. Both the emissions levels and the on-going real-time monitoring were prescribed by the EPA. For 1996 and later vehicles sold in the U.S., many of the monitored systems were required to have this feedback system to the operator.

What to do if this light comes on? Well, unless you have the proper equipment (OBD II scanner), you'll need to take it to a licensed repair facility to have the codes read and interpreted. Before you go to the shop however, make some notes:

- When did the light go on? How long ago (miles & date)

- Did you notice any other issues - performance, starting, engine miss, etc?

- Did you recently fill the fuel tank? - try re-tightening the fuel filler cap. It is the one thing (out of about 250 items) that you can check & fix on your own.