Skip the auto shop - Our mechanics make house calls

Q: Dodge Neon SE 2003 problem is code P0440

asked by on

hello, my problem is a code P0440 (Dodge Neon SE 2003)the black box and filter replacement(new),diagnostic all code is P0440 and Check Engine Light in instrument panel

The trouble code P0440 means the Evaporative emission control system is malfunction. This malfunction may have been caused by a number of different things including, a loose or missing gas cap, a vacuum leak, a faulty purge valve, an issue with your charcoal canister, incorrect fuel pressure, or electrical issues.

I would recommend having your entire EVAP system inspected by a mechanic who is proficient in diagnosing emissions issues. The most likely cause of this issue is either a loose gas cap or a vacuum leak.

Sometimes the issue is very obvious and may be spotted just by opening the hood. It is possible that a hose may have come loose causing the trouble code to be stored and the Check Engine Light to come on. For a proper diagnosis, consider YourMechanic, as a certified technician from YourMechanic can come to your car’s location to inspect the Check Engine Light and make proper adjustments or repairs.

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: Car has a hard time starting

Hello! On your particular vehicle, the hard start condition is commonly caused by a faulty fuel pump relay, fuel pump, or fuel filter, so I suggest checking the fuel pressure to determine if there is a problem with the fuel...

Q: Engine running rough - 2001 Ford F-150

Hi there. Have the codes returned since the repair? It sounds like the valve timing control valves are sticking. The valve timing control valves control oil flow to the valve timing actuator and are a duty cycle type controller. The...

Q: car burning oil

To begin, the Avensis is not sold in the United States. So if you live elsewhere, the laws and procedures in Europe for example, may be very different than they are here. But of course, fixing the car itself is...

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...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...