Skip the auto shop - Our mechanics make house calls

Q: Problem with emission control code P0440 Check Engine Light. Is that a major problem and how do you fix?

asked by on

is this a major fix where is the value located to fix?

My car has 1043270 miles.
My car has an automatic transmission.

Hi there,

A P0440 code is stored for an emission related fault; evaporative emission control malfunction. The evaporative emission system is responsible for preventing the release of fuel vapor into the atmosphere. When there is a fault in the system, it sets a corresponding code. This code could be the result of a mechanical or electrical malfunction. Electrical being a fuse, wiring, vapor sensor, or switching valve fault. Mechanical being a switching valve, mechanical valve, or a simple gas cap fault. This will not affect the vehicle’s performance, but needs to be addressed especially if you live in an area that performs emission inspections. Your mechanic has several available technicians to assist you with a Check Engine Light inspection and provide you with a detailed estimate and direction of repair.

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!
  • Home
  • Questions
  • Problem with emission control code P0440 Check Engine Light. Is that a major problem and how do you fix?

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 car stalls arbitrarily and with no warning and is getting progressively harder to start.

Hello and thank you for contacting YourMechanic. The code P1684 means that there was a battery disconnect from a sensor to the computer, or in other words, a sensor has lost communication with the computer. The code P0420 usually means...

Q: Car waits a bit to start

In order for the starter to engage on this vehicle, the computer needs to disable the anti-theft system. Then the computer will signal the totally integrated power module (TIPM) to activate the starter relay, then the starter can begin to...

Q: Top makes high-pitched noise when moved - 2004 Cadillac XLR

This is probably the correct advice. The retractable top pump and fluid reservoir is behind a carpeted panel (left, rear trunk area). Your Owners Manual should show the reservoir (Max/Min marks) and indicate the correct GM fluid to top it...

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...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...