P0446: Evaporative emission control system malfunction

Hey all.

For the last few months my MIL has been coming on after I fill the gas tank. I didn't think much of it because it kept going out on its own. Now it's staying on, so I dug out my OBD code reader and hooked it up. It gave me P0446.

I did some research and found it's most likely caused by a plugged charcoal filter. I assume this is because I have been overfilling my tank a lot lately because the nozzle at the pump always shuts off immediately after I lock the trigger. It sounds like gas keeps bubbling up the pipe for some reason. I have to manually hold the trigger down, so I never know if it's clicking off because the tank is actually full or not.

My question is, why do you think the gas keeps bubbling up? Also, where is the charcoal filter, and how do I replace it?

Notice you are putting in alot more gas than usual? I say this because gas pumps are designed with 2 nozzles, one for delivering the fuel and one smaller one that sucks air. If the one that sucks air suddently sucks fuel, it shuts off the pump telling you the tank is full. Now if you hold it past this point, basically the fuel is just getting sucked back into the service stations tanks and you are paying for it. So when it clicks off dont try and round up to the $ because you arent getting any more fuel but youre paying for it. In your case something is restricting the fuel flow and off hand the only thing i can think of is a kinked filler neck (if rubber) or a clogged filter/anti syphon screen. It sounds like you're on the right track with the code,

this taken from:http://wiki.answers.com/Q/What_does_OBDII_code_P0446_Evaporative_emissions_c ontrol_vent_circuit_low_mean

"Below are what I consider the possible causes of P0446 in the order of least likelihood (IMO) for a vehicle used in a high dust environment:
Electrical vent driver circuit in computer burned out (especially if the vent valve is shorted), electrical vacuum valve driver circuit burnt out, vent valve coil open or shorted, vacuum valve coil open or shorted, bad vacuum sensor in the gas tank, vent valve filter clogged with dust, charcoal cannister clogged with dust or residues."

I had to replace the vent tube that runs from the tank to the filler on my father in laws 99 Intrigue due to it being rotten, leaking gasoline and setting a code. The salt they use on the roads here caused this to happen. I just replaced it with a rubber hose and it has been fine since.

If you pump when the fuel light comes on thiers 13.5 gallons to fill Im sure its about thier on a 17.5 gallon tank 4 gallons in reserve. Also I leave the ignition on to let the guage rise as I pump and leave the gas nozzle clicked and snug with the car. It gets full all the time and I have got over 100-110miles off the first 4/4 tank quite a few times most highway

2000 Intrigue gx

Thanks for the replies. The filling problem seems to be getting worse. I just filled up again today and it's getting to the point where I can't get gas to go down without having to pause for 3 seconds every 5 seconds.

I checked the tubes, nothing looks kinked or rotted. I guess I'm going to have to dig a little deeper...

That is really weird. I would see about running something down the vent tube to see if it is blocked. I am not sure where everything terminates, but am assuming at the sender, which is located under a removable cover in front of the spare tire in the trunk, just behind the back seat. I cannot see how it would be plugged, but that would be a cheap check to do first.

This is a good one! Not sure what to suggest other than that. If you find anything let us know.