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Q: Car failed emissions test

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I took my car to get an emissions test and it failed due to various trouble codes. The codes included a Map/Barometric Circuit Malfunction, an EVAP Vent Control Malfunction, and a Mass or Volume Circuit Malfunction. What do I need to have done to fix these codes?

Hi, to fix this problem you will need to replace the intake manifold gaskets. That will take care of the Barometric Pressure Sensor. I would inspect the exhaust gas recirculation (EGR) valve, since it may have been left open causing the pressure sensor to come on. Also, inspect the idle air control motor. This causes very low engine idle. If you need further assistance, I would recommend having a certified mechanic, such as one from YourMechanic, give your vehicle a comprehensive inspection in order to have the repairs needed to pass the emissions test.

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