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Q: Check engine light is on, need help with codes

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A couple months ago, the Check Engine Light came on, and I took it to Auto Zone who helped me to retrieve the codes. Two codes came back about the gas cap being loose, so I tightened it. I know with Jettas, most of the warning lights have to be turned off by hand. I didn't do that, and figured I would have my car inspected later. So I did, and then the mechanic who tried looking at the car said that too many codes are showing up to pass it. I went to Auto Zone again and now the diagnostic tool came back with 7 codes. Here are the codes:

• P0456 Evaporative Emission System Leak Detected (Very small leak) • P0442 Evaporative Emission System Leak Detected (Small Leak) • P0441 Evaporative Emission System Incorrect Purge Flow • P0456 Repeat • P0442 Repeat • P0456 Repeat • P0442 Repeat

I have tried researching this but I am not able to find out the cause of this. Any suggestions? Can this be fixed at home?

A: What is most likely happening is that you h...

What is most likely happening is that you have a small vacuum leak somewhere.

There are many small vacuum lines in the emissions control system. I would recommend having a mechanic who is proficient in emissions diagnostics take a look at your vehicle to check for vacuum leaks with a small scale highly accurate vacuum gauge.

If the vacuum readings are low, the mechanic will then inspect your vacuum lines for any holes or cracks that could be causing this issue. Once the vacuum leak has been found, the hose would be replaced upon your request. YourMechanic offers technicians who can perform services like this at your home or business.

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