P0440 engine code only

code is a malfunction with the EVAP system. check the things below. bad gas cap, leaking fuel tank, charcoal canister is broken, faulty vent control valve, bad canister purge valve or loose or broken hose (EVAP) Good luck Mike L.

You may need a repair shop. Code 440 means the computer has found a leak in the venting system for the gas tank.
The problem could be the gas cap, a rubber hose, or a valve between the tank and the vapor canister.

Now have a repair shop do the proper testing & resolve

Need system diagrams,scan tool & evap smoke machine

You must have a leak somewhere in the tank, because gas caps seal and vent at a certain pressure (1-2psi) a smoke test would check it. Try clearing the code first. If it keeps comming up, test it.

P0440 - Evaporative Emission Control System Malfunction

This indicates that a part of the EVAP control system is no longer fuctioning correctly. The EVAP system consists of many parts, including (but not limited to) the gas cap, fuel lines, carbon canister, purge valve, and other hoses. The (EVAP) emission control system prevents the escape of fuel vapors from a vehicle's fuel system. Fuel vapors are routed by hoses to a charcoal canister for storage. Later, when the engine is running a purge control valve opens allowing intake vacuum to siphon the fuel vapors into the engine.

Symptoms: You likely won't notice any drivability problems.

Causes: A code P0440 could mean one or more of the following has happened:
The gas cap is not installed or working properly
The purge solenoid has failed
The canister is plugged and not working properly

Possible Solutions: With a P0440 OBD-II trouble code, diagnosis can be tricky at times. Here are some things to try:
Remove and reinstall the gas cap, clear the code, and drive for a day and see if the codes come back.
Inspect the EVAP system for cuts/holes in tubes/hoses
Inspect for damaged or disconnected hoses around the Evap purge solenoid
Check and/or replace the sensor
Check and/or replace the purge valve
Have a professional use a smoke machine to detect leaks

Hope helps.

A code P0440 could mean one or more of the following has happened:

• The gas cap is not installed or working properly
• The purge solenoid has failed
• The canister is plugged and not working properly

With a P0440 OBD-II trouble code, diagnosis can be tricky at times. Here are some things to try:

• Remove and reinstall the gas cap, clear the code, and drive for a day and see if the codes come back.
• Inspect the EVAP system for cuts/holes in tubes/hoses
• Inspect for damaged or disconnected hoses around the Evap purge solenoid
• Check and/or replace the sensor
• Check and/or replace the purge valve
• Have a professional use a smoke machine to detect leaks

Get a new gas cap first to try.
thanks

code p 0440 refers to the EVAP system --purge valve malfunction
check wiring and replace the purge valve

What does that mean?
This indicates that a part of the EVAP control system is no longer fuctioning correctly. The EVAP system consists of many parts, including (but not limited to) the gas cap, fuel lines, carbon canister, purge valve, and other hoses. The (EVAP) emission control system prevents the escape of fuel vapors from a vehicle's fuel system. Fuel vapors are routed by hoses to a charcoal canister for storage. Later, when the engine is running a purge control valve opens allowing intake vacuum to siphon the fuel vapors into the engine.

Possible Causes:
A code P0440 could mean one or more of the following has happened:

• The gas cap is not installed or working properly
• The purge solenoid has failed
• The canister is plugged and not working properly

Possible solutions:
With a P0440 OBD-II trouble code, diagnosis can be tricky at times. Here are some things to try:

• Remove and reinstall the gas cap, clear the code, and drive for a day and see if the codes come back.
• Inspect the EVAP system for cuts/holes in tubes/hoses
• Inspect for damaged or disconnected hoses around the Evap purge solenoid
• Check and/or replace the sensor
• Check and/or replace the purge valve
• Have a professional use a smoke machine to detect leaks

HTH,

Mike...

I am not going to lie, I came across this in another forum a while back and I would love to retype it and interpret it here but it is too much. I looked at it and verified that the information here is information that could be found through my scan tools so here it is!

P0440
The fuel tank pressure is atmospheric pressure after the vehicle is driven for 20 min (2 trip detection logic).

Possible Problems
Fuel tank cap incorrectly installed <= Most common
Fuel tank cap cracked or damaged (Toyota part only)
Bad vapor pressure sensor/circuit
Vacuum hose cracked, holed, blocked, damaged or disconnected 
Hose or tube cracked, holed, damaged, or loose
Fuel tank/filler neck cracked, holed, or damaged
Charcoal canister cracked, holed, or damaged (collision)

In above description, check hoses between vapor pressur sensor and VSV for vapor pressure sensor and charcoal canister. Also, hose between charcoal canister and fuel tank.

p0440 code means that the evap system has a leak. This could be caused by a bad or improperly installed gas cap. Either that or the purge solenoid has failed or the canister is plugged and not working properly.