How do I fix???

[crager34]

P0446
EVAP System Canister Vent Blocked (Except 2.2L)

EVAP System Canister Vent Control Circuit Malfunction (2.2L)


I made sure it wasn't the gas cap issue first. I had the Check Engine reset and it came back two days later. Does anyone know the lay terms for what is above?

[Joe_Black]

A couple things could be going on, but they're centralized around the charcoal canister underneath the VX just in front of the fuel tank on the fuel-filler side. There's a solenoid valve and the canister itself that could be at fault. The solenoid could be faulty, failing to switch the vent lines as needed, or the canister could be bad. If you overfill the tank times it could flood the canister. There is also a possibility of a sensor issue or perhaps the associated lines, but the two above are the most common.

In the CD shop manual there is detailed information on the canister and how to troubleshoot the system.

[Hotsauce]

Gross overfilling can flood the canister with gas. Carbon particles could then either clog the canister vent line, or block the solenoid vent valve.

The valve is located at the front of the lower manifold. Along the drivers side valve cover theres a vent hose with a T fitting and service cap that leads to the valve.


John C.

[crager34]

I am fairly certain I don't overfill. I fill up till the pump clicks off, then do that one more time after I wait about 5 seconds. I usually get about 1-2 more gallons in there too.


I have a long drive either tomorrow or Wednesday, so gonna try and get it fixed tomorrow. If I can't get it fixed, does anyone know if it's ok to drive it like this? It reminds me of the older cars where they didn't have the vents and you take the gas cap off and ppsshhhhhhhhhh!! This is what mine is doing. Are these items easily cleaned or replaced?

AND!! I have done everything I can to get Tone's CD manual to run and I can't. It keeps telling me to put the CD in, and it's there. I also have all the files loaded on the PC.

[kpaske]

The trick to getting Tone's CD to work is correctly setting the volume label on the disk when you burn it. I think the correct volume label is "vcross00" but don't quote me on that. I'll double check my CD for you when I get home if you want, or someone else can chime in.

As far as overfilling, I let it go until it clicks and leave it at that. I've never had any issues with that charcoal canister, FWIW.

[crager34]

Yeah. Someone's gonna have to chime in about the CD cause the simple intructions from his website don't make sense. "Must burn to CD named same as folder downloaded - VX00ESI1" First off you download a zip "file", not a folder. I named the CD VX00ESI1 and the folder where all the files reside the samd as well. Still not working. :(

I am still trying to find out if the VX is drivable with this issue, or is my gas tank going to blow up from the pressure?

[Joe_Black]

Your fuel tank won't blow up from pressure, mostly since you'll be removing a volume of fuel as you drive. The charcoal and evaporator stuff is emissions related and isn't necessary, but of course will cause issues just by being there. :p

[crager34]

After working with Merlin from St. Charles Isuzu, I finally got the issue resolved. Here is the Part and part number that took care of it:

Here’s a summary of the problem for P0446:



“An incorrect fuel tank pressure sensor signal is detected by monitoring fuel tank pressure when the key is first turned "ON" during a cold start. If the fuel tank pressure signal is out of range, DTC P0446 will set. A restricted or blocked EVAP vent path is detected by monitoring fuel tank pressure during normal operation (EVAP canister vent solenoid open, EVAP canister purge solenoid normal). With the EVAP canister vent solenoid open, vacuum level in the system should be very low unless the vent path is blocked. A blockage can be caused by the following condition:

Faulty EVAP canister vent solenoid (stuck closed).
Plugged, kinked or pinched vent nose.
Shorted EVAP canister vent solenoid driver circuit.
Plugged evaporative canister.
If any of these conditions are present, DTC P0446 will set.”



- So, the “EVAP canister vent solenoid” on your Vehicross is located at the rear of the vehicle:



The replacement solenoid includes the ‘filter’ you see attached in the picture. After confirming the vent hoses are not damaged or crimped, you may elect to replace this part. It is Isuzu part #8-97130-368-0, list price $118.69, your cost $100.89.

[Hotsauce]

https://www.trademotion.com/shoppingcart/index.cfm?action=addItem&return=accessory&siteid=214304&partid=2998769&make=15&partname=Cut%2Doff%20valve%201999%20%2D%202001&catalogid=2

$89.49

[crager34]

So I paid a couple dollars more, as shipping was free. Good find though.

[ScottinMA]

Well, stopped by Auto Zone and run my code from the check engine light. P0446. Was wondering whether the part purchased from Marlin solved the problem and whether a non-mechanic type can do this job?

[Gussie2000]

A couple things could be going on, but they're centralized around the charcoal canister underneath the VX just in front of the fuel tank on the fuel-filler side. There's a solenoid valve and the canister itself that could be at fault. The solenoid could be faulty, failing to switch the vent lines as needed, or the canister could be bad. If you overfill the tank times it could flood the canister. There is also a possibility of a sensor issue or perhaps the associated lines, but the two above are the most common.

In the CD shop manual there is detailed information on the canister and how to troubleshoot the system.

Yes,this is the most common issue,i had my canister replace last year,the engine light still comes on,but the mech said got to be a ECU wire that is faulty.but since is so many possible causes you got to test all related components to figured which is the real cause of the malfunction

[Gussie2000]

I am fairly certain I don't overfill. I fill up till the pump clicks off, then do that one more time after I wait about 5 seconds. I usually get about 1-2 more gallons in there too.


I have a long drive either tomorrow or Wednesday, so gonna try and get it fixed tomorrow. If I can't get it fixed, does anyone know if it's ok to drive it like this? It reminds me of the older cars where they didn't have the vents and you take the gas cap off and ppsshhhhhhhhhh!! This is what mine is doing. Are these items easily cleaned or replaced?

AND!! I have done everything I can to get Tone's CD manual to run and I can't. It keeps telling me to put the CD in, and it's there. I also have all the files loaded on the PC.

You can drive the VX with no problem,is doesn't harm the performance,but if you got to inspected it wouldn't pass emission test,that's all

[Jolly Roger VX'er]

Yes,this is the most common issue,i had my canister replace last year,the engine light still comes on,but the mech said got to be a ECU wire that is faulty.but since is so many possible causes you got to test all related components to figured which is the real cause of the malfunction

Mine trips about once, twice a month. I found the wire for it going to the tank and it was broken. I repaired the wire and voila...code still trips once, twice a month. :confused:

Lately, it's been behaving itself and hasn't been on for about a month. I have been guilty in the past of over-filling with gas...perhaps since I've been very careful as of late, things are looking up :rolleyes:

[Gussie2000]

Well, stopped by Auto Zone and run my code from the check engine light. P0446. Was wondering whether the part purchased from Marlin solved the problem and whether a non-mechanic type can do this job?

That was the same code that my ECU pop up when i run a OBD test,so yes,go for the canister,also the vent solenoid should be replaced together.

Theres' a possibility that EVAP lines can be clogged or rusted,sensors shall be considered in the equation.

[ScottinMA]

You can drive the VX with no problem,is doesn't harm the performance,but if you got to inspected it wouldn't pass emission test,that's all

And there lies my problem. Must get it fixed to pass emissions..

[ScottinMA]

Just purchased the parts from Marvin, a canister and valve for a little over $200. I decided to crawl under it yesterday and do the replacement and the check engine light goes off! This truck is playing with me. It did get warmer and I wonder whether temp may play a part in this saga. So, my plan is to drive around with the parts in the back seat cause I know the moment I put them in the garage the check engine light will come back on.

[Gussie2000]

Hahahaha that's so funny though.:)

Actually,after replacing the canister my engine lit was still popping on,however,after my mech worked on the engine the lit didn't came on any more.

Now,there's something you got to know,you must replace both vent solenoids the one located at the rear & the other located right under where the intake pipe conects to the intake manifold.

I'll also go almost tank empty to eliminate all vapors in the fuel tank before the ECU is reset.

[ScottinMA]

Sounds good..thanks Gussie