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don't panic: it's just a warning light

When the “Check Engine” light stays on, so does the car owner’s imagination. The vague phrase can indicate serious trouble for sure, but it might also mean there’s something easily fixed without a trip to the mechanic shop.

One of the most common triggers is an emission control problem – the smog-control system designed and installed in every new car for more than 20 years. Faulty or clogged oxygen sensors often trigger the light, and you’ll need to replace the sensor. Yes, for that you’ll need a professional mechanic and a fat wallet.

However, before you take your vehicle to the shop, make sure the light’s not being triggered by something simple. After all, it’s just a warning that there’s something, anything, working imperfectly under the hood. There are three common things that might activate the light:

Loose gas cap
You know that little sign on your gas flap that says you should turn the cap and listen for at least 3 clicks when tightening it? That’s important to do. If the engine senses a change in pressure in the gas tank because of a loose cap, it may light “the light.” Remove the cap, replace it and turn it a few clicks extra this time, and wait about a week, or through the next fill-up. The light may be doused.

Bad sparkplug wires
Aging sparkplug wires often develop tiny cracks which lead to small misfires and a minor “alarm” for the “Check Engine” sensor. Turn off your engine and inspect your sparkplug wires for little holes or cracks at the end of the wires, and replace any of them that look questionable.

Wet engine
Are you the kind of car or truck owner who likes to spray your engine to keep it clean and shiny? That high pressure wash may be triggering the Check Engine light. If that attention to cleanliness isn’t your issue, check for another way rain or dripping water has gotten to your engine and correct the leak.

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