Skip the auto shop - Our mechanics make house calls

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

asked by on

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?

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.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: My truck runs till it gets warm then acts like it has no power.

Hi there. It seems that your vehicle has multiple malfunctions that are happening at the same time. The idle air control valve has a fault, evaporative emission system has a large leak, the gear ratio is incorrect, and knock sensor...

Q: why wont my car pass smog

There are many components that work together to ensure your vehicle produces low emissions. It can be something as simple as a vacuum leak or faulty PCV valve, or even a faulty oxygen sensor or catalytic converter. If you didn't...

Q: Can a purge solenoid cable cause a EVAP leak code?

Hi, thanks for your question. When the engine is off, the vent shutoff valve and canister purge valve are closed. The fuel can't escape into the atmosphere. When the engine starts, the purge valve on the canister opens to allow...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...