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blondiez24gt
10-19-2008, 01:16 PM
My car is running fine. But this morning while I was driving my service engine soon light pops up. So I pull in to auto zone to get it scanned. It says; The PCM has determined that a malfunction exists in the evaporative emission control system. The code is P0440. The definition was EVAP (evaporative emission system) small leak/no flow condition. Explanation being The evaporative emission system is monitored probable causes:

1. Defective or loose fuel cap
2. EVAP canister or hose cracked-not connected.
3. Purge or vent solenoid defective.
4. Vacuum leak at engine.

I wouldn't think that it would be a vacuum leak because my car is running fine. I was just wondering what to do. I checked my fuel cap, it is tight. Someone please let me know what I should do or what this could be. Thanks a lot.

hass
10-19-2008, 01:42 PM
Did you get gas recently?
Has to be turned on at least 3 clicks.
It will take a ton of cold starts in order for the light to go off if it was the gas cap.

TFA
10-19-2008, 01:52 PM
reference my thread SVS light vs. SES light, its less than a week old and the same exact topic. my light went off 2 days later, hasent been on since.

blondiez24gt
10-19-2008, 08:18 PM
I went out and unscrewed the gas cap, and put it back on really good( about 6 clicks! hehe). I started the car and shut it off a few times. It didn't do anything. I went back in the house, and a little bit later I had to go to the store. When I started it up the light wasn't on, and it never came back on the whole time I drove it. So hopefully it stays off.

Mike Jung
10-19-2008, 08:48 PM
I went out and unscrewed the gas cap, and put it back on really good( about 6 clicks! hehe). I started the car and shut it off a few times. It didn't do anything. I went back in the house, and a little bit later I had to go to the store. When I started it up the light wasn't on, and it never came back on the whole time I drove it. So hopefully it stays off.
^
The car needs at least 2 cold starts in a row, where the computer detects no problems for the light to go off.

If it was a loose gas cap.

Cliff8928
10-20-2008, 12:34 AM
DTC P0440 Evaporative Emission (EVAP) System

System Description

For a more complete overview and system description, refer to Evaporative Emission (EVAP) Control System Operation Description .

The evaporative system includes the following components:

The fuel tank.
The EVAP vent valve/solenoid.
The fuel tank pressure sensor.
The fuel pipes and hoses.
The fuel fill cap.
The EVAP vapor lines.
The EVAP purge lines.
The EVAP canister.
The EVAP canister purge valve/solenoid.
The EVAP LARGE LEAK TEST Is based on applying vacuum to the EVAP system and monitoring vacuum decay. The PCM monitors vacuum level via the Fuel Tank Pressure Sensor input. At an appropriate time, the EVAP canister purge valve/solenoid and the EVAP vent valve/solenoid are turned on, allowing engine vacuum to draw a small vacuum on the entire evaporative emission system. If a sufficient vacuum level cannot be achieved, a large leak or a faulty EVAP canister purge valve/solenoid is indicated. This can caused by the following conditions:

Disconnected or faulty fuel tank pressure sensor.
Missing, not completely installed or faulty fuel fill cap.
Disconnected, damaged, pinched, or blocked EVAP purge line.
Disconnected or damaged EVAP vent hose.
Disconnected, damaged, pinched, or blocked fuel tank vapor line.
Disconnected or faulty EVAP canister purge valve/solenoid.
Disconnected or faulty EVAP vent valve/solenoid.
Open ignition feed circuit to the EVAP vent or purge valve/solenoid.
Damaged EVAP canister.
Leaking fuel sender assembly O-ring.
Leaking fuel tank or fuel filler neck
Any of the above conditions can set DTC P0440.

Conditions for Running the DTC

No TP sensor, ODM, IAT sensor, or MAP sensor DTCs set.
System voltage is between 9 and 16 volts.
Startup engine coolant temperature is between 4C and 30C (40F and 86F).
Startup engine coolant temperature is not more than 8C (14F) greater than startup intake air temperature.
Startup Intake air temperature is between 4C and 30C (40F and 86F).
Startup intake air temperature not more than 2C (4F) greater than start-up engine coolant temperature.
Fuel tank level is between 15% and 85%.
BARO is greater than 75kPa.
Conditions For Setting the DTC

The EVAP system is not able to achieve or maintain vacuum during the diagnostic test.

Action Taken When the DTC Sets

Important


Although this diagnostic is considered type A, it acts like a type B diagnostic. Whenever the EVAP diagnostics report that a system has passed, or if the battery has been disconnected, the diagnostic must fail during 2 consecutive cold start trips before setting a DTC. The initial failure is not reported to the diagnostic executive or displayed on a scan tool. A passing system always reports to the diagnostic executive immediately.

The PCM will store conditions which were present when the DTC set as Freeze Frame data.
The PCM will store conditions which were present when the DTC set as Fail Records data.
Conditions for Clearing the MIL/DTC

The PCM will turn the MIL OFF when the diagnostic has been run and the fault condition is no longer present.
A history DTC P0440 will clear after 40 consecutive warm-up cycles have occurred without a fault.
This DTC can be cleared by using the scan tool Clear Info function or by disconnecting the PCM battery feed.
The code will clear if the fill cap is tightened or Reinstalled.
Diagnostic Aids

Check for the following conditions:

Cracked or punctured EVAP canister.
Damaged or disconnected source vacuum line, EVAP purge line, vent hose or fuel tank vapor line.
Poor connection at the PCM.
Inspect harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connection.
Damaged harness. Inspect the wiring harness to the EVAP vent valve/solenoid, the EVAP purge valve/solenoid, and the fuel tank pressure sensor for an intermittent open or short circuit.
Kinked, pinched or plugged vacuum source, EVAP purge, or fuel tank vapor line. Verify that the lines are not restricted.
Use the following procedure to check for a carbon release condition that could plug the system.
Turn off the ignition switch.
Remove the EVAP canister purge valve/solenoid. Refer to Evaporative Emission (EVAP) Canister Purge Valve Replacement .
Lightly tap the canister purge valve on a clean work area looking for carbon particles exiting either of the vacuum ports.
If no carbon release is evident, reinstall the components and continue with the DTC P0440 diagnostic table. If carbon is being released from either component, continue with this service procedure.
Remove the charcoal canister from the vehicle.
Ensure that the main cylinder valve is turned off on the J 41413 EVAP purge/pressure diagnostic station.
Disconnect the black hose that connects the nitrogen cylinder to the EVAP purge/pressure diagnostic station at the pressure regulator by unscrewing the knurled nut on the regulator. No tools are required to remove the black hose from the regulator.
Using a section of vacuum line, connect one end over the open threaded fitting of the EVAP purge/pressure diagnostic station pressure regulator.
Connect the remaining end to the purge valve end of the EVAP purge line at the vehicle and turn on the main nitrogen cylinder valve. Continue to blow any debris from the purge line for 15 seconds.
Return the EVAP Pressure/Purge Diagnostic Station to its original condition by reinstalling the black hose that was disconnected in step 7.
Replace the following components:
The EVAP canister purge valve. Refer to Evaporative Emission (EVAP) Canister Purge Valve Replacement .
The EVAP canister. Refer to Evaporative Emission (EVAP) Canister Replacement EVAP Canister.
Proceed with the DTC P0440 diagnostic table..

Kyle
03-14-2009, 10:01 AM
Where is the canister located?

AaronGTR
03-14-2009, 10:44 AM
Underneath the car. Looks like a big black rectangular box with an aluminum cover on one end and a bunch of tubes connected to the other. Bolts up to the chassis directly behind the gas tank and in front of the rear suspension cradle.

Kyle
03-15-2009, 06:19 AM
Thanks alot!

Attridge 300ZX
03-30-2010, 05:27 PM
Does anyone have a picture, or diagram of the EVAP Canister which shows the route of hoses. I believe that I may have a hose disconnected. There is a crap load of grease and gunk all over the EVAP Canister. My car failed it's E-test last week because of the NO ppm being almost double. My car was trowing a SES that was EVAP system leak, didn't think it would make me fail the test, but I guess it did. I had a smoke test run and it showed a faulty gas cap. So I replaced it, and hope that was the only issue, but I think it has to be more then that, that caused me to fail.