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Q: Car failed emissions test

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My car failed an emissions test.

A: Your truck can fail an emissions test for a...

Your truck can fail an emissions test for a number of reasons. If I knew the results of the inspection I could give you some common causes of this failure. If the vehicle failed the visual check then there may be a part that is missing or not functioning as designed. If it failed the HC test then it may have a misfire or a failing catalytic converter. If it failed the NOX test then the EGR system may have a problem. A mechanic would need to know the results of the test in order to know where to start the diagnostic process.

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