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?

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.

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・Save up to 30%

Get a quote

What others are asking

Q: Truck making rattling sound underneath

Hi. The issues are probably unrelated. The first step in diagnosing your Check Engine Light is to retrieve the diagnostic trouble codes (DTCs). There are countless reasons your Check Engine Light may be on, and these codes serve as a...

Q: Car shuts off when the weather is hot

Hello. A bad cam position sensor will cause a Check Engine Light to come on and possibly cause a stall or no start condition for your 2000 Mercury Mystique. Cam position sensors usually develop their problems when hot, so this is likely...

Q: Truck made a screeching sound and then warning lights came on

Wow, Tacoma's are good trucks and yours is pretty new. I'm surprised to hear your story. Anyhow, the variable valve timing system in your vehicle is oil pressure dependent and the codes you found are related to valve timing. In...

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...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.