Codes 446 and 452

There is no such thing , What code do you have if any ? There is a purge solenoid for the EVAP system ! evaporative emission system. An there is a vent solenoid , a fuel tank pressure (FTP) sensor.
The evaporative emission (EVAP) control system limits fuel vapors from escaping into the atmosphere. Fuel tank vapors are allowed to move from the fuel tank, due to pressure in the tank, through the vapor pipe, into the EVAP canister. Carbon in the canister absorbs and stores the fuel vapors. Excess pressure is vented through the vent line and EVAP vent valve to atmosphere. The EVAP canister stores the fuel vapors until the engine is able to use them. At an appropriate time, the control module will command the EVAP purge valve ON, open, allowing engine vacuum to be applied to the EVAP canister. With the EVAP vent valve OFF, open, fresh air will be drawn through the valve and vent line to the EVAP canister. Fresh air is drawn through the canister, pulling fuel vapors from the carbon. The air/fuel vapor mixture continues through the EVAP purge pipe and EVAP purge valve into the intake manifold to be consumed during normal combustion. The control module uses several tests to determine if the EVAP system is leaking.

PO 446 Evap System Vent Solenoid issue

Nothing to do with the canister

Have to test parts & only replace those that fail

Smoke the system & test all the evap components

Scan tool data may help

Google your codes

Type: OBD PO446

No --- you need to use the Evap Codes to component
test the Canister & System--- to find a problem

Codes have nothing to do with replacing parts

You may find a picture on the internet if you use the search
engine correctly & ask the right questions

The IAT sensor is located in the air filter case on top of the throttle body. If you remove the air filter you can see it on the left side of the case on the bottom. It connects from underneath and the connector can easily be damaged if you are not careful when removing the lower part of the air filter housing from the throttle body. If you replaced the MAP sensor you may have damaged the connector or pulled a wire loose.

The p1447 problem indicates a leaky evap system which could be as simple as a bad gas cap or as in my case a bad evap canister and vacuum canister cut/bypass valve.(http://ww2.justanswer.com/uploads/fixurnissan/2012-02-04_230002_1.pdf)

If your evap canister has ruptured then your evap lines will be full of carbon pellets. You will need to disconnect each end (evap canister line towards front) and evap canister purge line towards the rear and blow out these lines with compressed air. Once they are clear replace the evap canister and check the vacuum canister cut/bypass valve as described in the link. If you fix this your self you will save close to $1000 as opposed to what a dealer would charge to fix this problem.

code p0441 refers to evaporative emission EVAP system-incorrect flow detected===causes hose connections--intake leak---EVAP canister purge valve
Po144 refers to the same fault and causes
Po446 refers to EVAP system--vent control-circuit malfunction===causes --wiring---EVAP canister purge valve---ECM In all cases codes the canister purge valve gets a mention and then the ECM. I would take it back and ask that the canister purge valve be changed or even ask for a new canister as there are occasions when filling the tank to the filler hole will induce fuel into the canister causing it to malfunction.

getting code p441 could be caused by evap purge solenoid vacuum line loose leaking or restricted, evap purge solenoid faulty, evap purge vacuum line to canister leaking or disconnected,evap canister failed.

Hi, the computer has sensed through the fuel tank pressure sensor that the vapor cannister is not evacuating properly. I have pasted details on the EVAP system below. Check the purge valve on top of the engine as shown below (#1 in picture). Make sure the electrical connector is on the valve, that the wires are not damaged, and check the hose for kinks. If all looks good, I recommend you replace the valve. A new valve is $23 at autozone. Please let me know if you have more questions and thanks for using FixYa.


Description & Operation
EVAP Canister
The canister is filled with carbon pellets used to absorb and store fuel vapors. Fuel vapor is stored in the canister until the control module determines that the vapor can be consumed in the normal combustion process.
EVAP Control System
The evaporative emission (EVAP) control system limits fuel vapors from escaping into the atmosphere. Fuel tank vapors are allowed to move from the fuel tank, due to pressure in the tank, through the vapor pipe, into the EVAP canister. Carbon in the canister absorbs and stores the fuel vapors. Excess pressure is vented through the vent line and EVAP vent solenoid to atmosphere.
The EVAP canister stores the fuel vapors until the engine is able to use them. At an appropriate time, the control module will command the EVAP purge solenoid ON, open, allowing engine vacuum to be applied to the EVAP canister. With the EVAP vent solenoid OFF, open, fresh air will be drawn through the solenoid and vent line to the EVAP canister. Fresh air is drawn through the canister, pulling fuel vapors from the carbon.
The air/fuel vapor mixture continues through the EVAP purge pipe and EVAP purge solenoid into the intake manifold to be consumed during normal combustion. The control module uses several tests to determine if the EVAP system is leaking.
The EVAP system consists of the following components:
EVAP Purge Solenoid
The EVAP purge solenoid controls the flow of vapors from the EVAP system to the intake manifold. This normally closed solenoid is pulse width modulated (PWM) by the control module to precisely control the flow of fuel vapor to the engine. The solenoid will also be opened during some portions of the EVAP testing, allowing engine vacuum to enter the EVAP system.
EVAP Service Port
The EVAP service port is located in the EVAP purge pipe between the EVAP purge solenoid and the EVAP canister. The service port is identified by a green colored cap.
EVAP Vent Solenoid
The EVAP vent solenoid controls fresh airflow into the EVAP canister. The solenoid is normally open. The control module will command the solenoid closed during some EVAP tests, allowing the system to be tested for leaks.
Fuel Tank Pressure Sensor
The FTP sensor measures the difference between the pressure or vacuum in the fuel tank and outside air pressure. The control module provides a 5-volt reference and a ground to the FTP sensor. The FTP sensor provides a signal voltage back to the control module that can vary between 0.1-4.9 volts. As FTP increases, FTP sensor voltage decreases, high pressure = low voltage. As FTP decreases, FTP voltage increases, low pressure or vacuum = high voltage.

P1447 - Evaporative Emission (EVAP) Control System, Purge Flow Monitor
In this evaporative emission (EVAP) control system, purge flow occurs during non-closed throttle conditions. Purge volume is related to air intake volume. Under normal purge conditions (non-closed throttle), the EVAP canister purge volume control solenoid valve is open to admit purge flow. Purge flow exposes the EVAP control system pressure sensor to intake manifold vacuum.

Under normal conditions (non-closed throttle), sensor output voltage indicates if pressure drop and purge flow are adequate. If not, a fault is determined. Malfunction is detected when EVAP control system does not operate properly, EVAP control system has a leak between intake manifold and EVAP control system pressure sensor.

Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)

Possible causes
* EVAP canister purge volume control solenoid valve stuck closed
* EVAP control system pressure sensor and the circuit
* Loose, disconnected or improper connection of rubber tube
* Blocked rubber tube
* Cracked EVAP canister
* EVAP canister purge volume control solenoid valve circuit
* Closed throttle position switch
* Blocked purge port
* Closed throttle position switch


Test is and send us your updated.

i just went through that problem

Evap canister / close solenoid and air filter $211- 230.00 in parts

$675- $71.00 at dealships for this small 30 minute task

If no check engine light Evap canister and air filter - fixxes problem 100 %
note:you may be able to get by just replacing air filter- works
rarely

if have check engine- close solenoid and purge solenoid may need replace- you local autozone- like autozone will pull check codes for free

the how to:

Jack car up in rear - behind right rear tire - canister -canister close solenoid & air filter are located in a plastic box with metal strap and one bolt.

Unscrew bolt everything drops down the EVAP CANISTER is held to plastic box by wirer tie . Remove wire tie and solenoid connection.
There is a small metal wire clip the holds the solenoid electrical connection together with a flat screw driver pry up the wire clip , off is okay too , ....it will go back on.

Once you have done all that you have full access there are i believe from memory 3 rubber hoses with clips ......Mark hose connects very important mark the hoses way the going on evap canister with color tape .

Next, remove whole assembly- the solenoid and air filter will come with the evap canister.

Now that have the whole assembly move to your work bench
look to see how the soleniod hook up to the canister and the air filter - now, disconnect the hose to black solenoid and remove the air filter which hook to solenoid and solenoid at same to ......

Next seperate the the solenoid and air filter- you should be air to put your mouth on solenoid and blew air in one hole and out the other- this solenoid is noramlly open- if air dosen't go threw is stuck closed and must be replaced.

same with air filter- this air filter are know for get plugged and should be replaced every 30,000 miles.

Also note: over fill you gas tank , at fill up - can cause the Evap to get liquid gas inside which cause the chorcoal in the filter to swell up and plyug the system up.------ you should when fill up stop pump gas after the auto pump click off on normal work tank and not try to top off you tank.

note: check with your deal for exact wieghts
weigh the evap canister - six pound - replace it- new one is about 4-4.5 pounds - it is just best to replace .The evap holds gas fumes then send to engine so that dosn't vent to

All parts are dealships only -

This is easy fix and normal, for gas fill problems

canister Evap 161.00
canister close solenoid 43.00 may or may not be used
air filter 7.00

not used in this fix- check engine fix use these parts
sensor price ?
purge valve 39.00
canister close solenoid 43.00

Could be the gas cap.  Do you fill the tank with the engine running?
Otherwise, check the hoses near the Evap canister.  I have 2003 T&C and had the small leak and large leak codes.  I looked at the evap cansiter and the hose coming from the fuel tank vapor line had a huge crack in it, to the point it had fallen off the evap caniser.  I trimmed the end of the hose and reconnected and voila, no codes.
The evap canister is on the driver's side of the van, underneath, slightly behind the drivers seat.
BTW, to clear the codes without an OBDII reader, remove the negative cable for 5-10 minutes (15 to be safe).  The computer resets and clears the codes, except for one that it sets saying loss of power to the memory.