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Is It Safe to Drive with the Check Engine Light On?

The Check Engine Light is tied into your car’s emissions system, and it’s designed to light up whenever something goes wrong with this complex collection of components and sensors. Is it safe to drive with the Check Engine light on?

  • If it comes on while driving: If the Check Engine Light comes on while you’re driving, it can be unnerving. Don’t panic, though. Take a moment to see if the car is driving any differently than normal. Is it bucking? Surging? Are there any unusual sounds? If nothing seems out of the ordinary, you can continue driving the car. It could be anything from a failed oxygen sensor to a bad MAF sensor. It could also mean that your catalytic converter has given up the ghost.

Regardless, you’re safe to drive for now as long as the car isn’t performing strangely. Just have the Check Engine Light checked and the problem repaired. Not repairing the problem can lead to more serious damage down the road (a failed oxygen sensor can eventually lead to catalytic converter damage, which is far more expensive to replace).

  • If it comes on after fueling up: While many current models have a “loose gas cap light”, older models didn’t come with this feature. If you left the gas cap loose or off, the computer would detect a leak in the evaporative emissions system and turn on the Check Engine Light. If the light comes on shortly after fueling up, check your gas cap. Take it off, and then re-install it. Drive the car for a while and see if the light goes out (note that it may take a couple of restarts of the engine to make the light go out).

If your car’s Check Engine Light is on, it means that there’s a problem somewhere in your emissions system. YourMechanic can check the codes that are stored in the car’s computer, make recommendations, and even provide repairs or part replacements.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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