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'Catalytic Converter Warning Banner'

Five Catalytic Converter Warning Signs

The catalytic converter is a vital part of your vehicle's emissions control system. Its job is to reduce toxic air by converting harmful pollutants into less harmful emissions such as water, carbon dioxide and nitrogen.

The best thing you can do is be aware of trouble signs and head to a service facility if you suspect a malfunction.

5 Signs of a Failing Catalytic Converter:

'Not accelerate when pedal Banner'

1. Your car doesn't accelerate when you step on the gas pedal The catalytic converter works with your vehicle's Powertrain Control Module (PCM) and other emissions control devices. If your catalytic converter isn't working properly, you will begin to have issues with your car's emissions system.

'Refuses to start or quits Banner'

2. Your car refuses to start or it quits after a few minutes If your vehicle is not starting or is experiencing a faulty start, you will need to go into your local service shop to get it tested. With our roadside assistance program, we make this process quick and seamless.

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3. The Check Engine light comes on The Check Engine light is the most ominous of the dashboard lights. If your check engine light comes on, there is a chance your catalytic converter is what triggered it. As with all automotive malfunctions it is best to have the vehicle evaluated by a professional and to familiarize yourself with your car's dashboard indicator lights.

'Fuel efficiency suddenly drops Banner'

4. Your car's fuel efficiency suddenly drops If you're starting to notice that you're frequenting the gas station more often, there is a chance you may need a service appointment for your catalytic converter. If that isn't it, visit our gas savings tip page to see if there's something else bringing down your fuel efficiency.

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5. Your car fails an emissions test Just like you need a yearly physical to ensure your good health, so does your beloved car or truck. An annual car inspection can help keep you on the road safely and help take care of any issues before something goes seriously wrong on the road.


The most common cause of failure in a catalytic converter in an older car is that it becomes so clogged that the exhaust gases can't get through it to the muffler and out of the car. If air can't get out the rear of the vehicle, it can't come in the front end, so the engine dies because no air is coming in to form the fuel/air mixture. Visit your local Pep Boys today if you think you may need a catalytic converter repair or replacement.

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