EVAP Codes: P0440, P0441, and P0442

EVAP codes are among the most common that car owners encounter. When you see a warning light on your car’s dashboard, the first thing you probably do is check the owner’s manual to find out which light it is. After that, you may want more information before you take it to an auto repair shop. The mechanical workings of a car can be complicated and you want as much knowledge as possible, so you’ll understand what the mechanic is referring to. It may also be the case that the warning light is for something that you or a friend may be able to fix.

What are EVAP Codes?

According to OBD Codes, EVAP codes represent codes for Evaporative Emission Control System malfunctions. There are many mechanical reasons for these codes. They indicate that a part of the Evaporative Emissions Control System is no longer functioning correctly. This system includes the gas cap, fuel lines, carbon canister, purge valve, and other hoses. Its purpose is to prevent the escape of fuel vapors from a vehicle’s fuel system. When the system is working correctly, those fuel vapors are routed by hoses to a charcoal canister for storage. Then, when the engine is running, a valve opens allowing the vapors to be siphoned into the engine.

What Does the P0440 EVAP Code Mean?

A code drivers commonly encounter is P0440. This code can mean one of several things. It could mean that the gas cap might not be installed or working properly. It can also mean that the purge solenoid has failed. The P0440 code could also mean the carbon canister is plugged or not working properly. You can try several options if you get this code. These include:
* Remove the gas cap and re-install it. This may mean buying a new gas cap.
* You can also have the EVAP system inspected for holes or cuts in hoses; also check for disconnected hoses.
* Consider replacing the sensor itself.
* Have a mechanic at an auto repair shop check for leaks using a smoke machine.

What Does the P0441 EVAP Code Mean?

The P0441 EVAP code means Evaporative Emission Control System Incorrect Purge Flow. There is a valve that controls when the emission purge canister empties stored fuel vapors from the fuel tank into the engine where they are burned. A switch detects when it is time to purge vapor. If the car’s computer sees the switch is closed, meaning there is no purge flow, it sets the P0441 code. The switch could be broken, or the EVAP line or canister could be damaged. In addition, the circuit controlling the process could be open or there may be a short in the system. These are only some of the possible mechanical reasons for the code. You may need to repair the lines or canister, or short in the voltage may need to be repaired.

What Does the P0442 Code Mean?

A P0442 code means Evaporative Emission Control System Small Leak Detected. This means there is a fuel vapor leak in the EVAP control system. It also means it is a very small leak. The leak could be as tiny as 0.04 inches in diameter. A loose or cracked gas cap can cause this code. Even an aftermarket gas cap, one that is not from the car’s manufacturer can cause a P0442 code. It can also be from a small leak or hole in a fuel vapor hose, tube or O-ring. Try removing and replacing the gas cap. If you are mechanically inclined, try inspecting the hoses, tubes, and O-rings. You may also want to take your car to an auto repair shop.

The EVAP codes on a car are often set off by things as simple as a loose or cracked gas cap. They will, however, cause a check engine light to alert the driver. The first thing to do is to check your owner’s manual. You may also take the car to an auto parts shop to have the codes read by a computer. All EVAP codes deal with the mechanical workings of your car. You may be able to repair what’s needed yourself while other problems may require a trip to an auto repair shop.