Pulled the code this morning - P0440
Thread Starter
Racer
Joined: Nov 2007
Posts: 262
Likes: 0
From: Pittsburgh PA
Pulled the code this morning - P0440
Well, I pulled the code this morning. It came up P0440. I know, before everyone tells me to check the gas cap, it is on tight. Any ideas what else it could be?
Le Mans Master
Joined: Aug 2006
Posts: 9,987
Likes: 25
From: If opportunity doesn't knock, build a door. South West Florida / Livin' The Dream
St. Jude Donor '12
Hers a little info on the code from the OBD-II web site.
P0440 OBD-II Trouble Code
Technical DescriptionEvaporative Emission Control System Malfunction
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.
SymptomsYou likely won't notice any drivability problems.
CausesA 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 SolutionsWith 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 this helps.
P0440 OBD-II Trouble Code
Technical DescriptionEvaporative Emission Control System Malfunction
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.
SymptomsYou likely won't notice any drivability problems.
CausesA 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 SolutionsWith 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 this helps.
Drifting
Joined: Jan 2008
Posts: 1,250
Likes: 0
From: Michigan
Hers a little info on the code from the OBD-II web site.
P0440 OBD-II Trouble Code
Technical DescriptionEvaporative Emission Control System Malfunction
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.
SymptomsYou likely won't notice any drivability problems.
CausesA 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 SolutionsWith 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 this helps.
P0440 OBD-II Trouble Code
Technical DescriptionEvaporative Emission Control System Malfunction
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.
SymptomsYou likely won't notice any drivability problems.
CausesA 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 SolutionsWith 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 this helps.
Premium Supporting Vendor
Joined: Oct 2004
Posts: 36,838
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From: Manassas Park VA
St. Jude Donor '07-'08,-'13-'14, '16-'17
Start with the gas cap. Just because it's on tight, does not mean it is not broken... I've had 2 on my 04
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Chip
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Chip
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Tech Contributor
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If not theres some great advice here.
Thread Starter
Racer
Joined: Nov 2007
Posts: 262
Likes: 0
From: Pittsburgh PA
Thanks guys for all the help and advice. I will be back home tomorrow so I will check the gas cap again for a good seal. I cleared the code so I will take it for a ride to see if it comes back.
Thanks again
Thanks again
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Drifting
Joined: Apr 2007
Posts: 1,496
Likes: 1
From: LEBANON PA.
Hi There,
A quick way to troubleshoot the gas cap.Take some duct tape, tape all around the base of the cap & trim off the excess carefully.Then reinstall the cap.
This will make a good seal for a temporary test.If the dic code disappears, then buy a new gas cap gasket. Do not leave the tape on more than a hour.It will melt.If you have a thin sheet of cork gasket material this will seal also.
robsc501
A quick way to troubleshoot the gas cap.Take some duct tape, tape all around the base of the cap & trim off the excess carefully.Then reinstall the cap.
This will make a good seal for a temporary test.If the dic code disappears, then buy a new gas cap gasket. Do not leave the tape on more than a hour.It will melt.If you have a thin sheet of cork gasket material this will seal also.
robsc501
