Q: Failed emissions test...need advice

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The following diagnostic trouble codes occurred during my emissions test: P0504 Brake Switch A/B Correlation, P0420 Catalyst System Efficiency Below Threshold Bank 1, P0464 Fuel level Sensor a Circuit Intermittent, and P0110 Intake Air Temperature Sensor 1 Circuit Bank. I need advice on what I should do and the services needed to fix these errors.

Hi...the codes appear to implicate different vehicle systems. As far as the required services, such will depend on exactly why the particular code has set. For example, resolutions of P0420 range from replacement of the converter to simply bad wiring connections on the oxygen sensor. So, what you need is a diagnostic to track down the exact cause behind each code. I recommend you request a check engine light diagnostic and the responding certified mechanic will get the underlying fault(s) identified, via a specific diagnostic, and resolved in the case of each code. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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