P0446 Evaporative Emission (EVAP) Vent System Performance

[Bosen_Sweden]

I have the OBD2 code P0446 Evaporative Emission (EVAP) Vent System Performance. Anyone who know what the problem could be???
Can it be the fuelcap??? if so, how can I check it???

[envoyxuv]

P0446 refers to the evaporative vent solenoid used to test the evap system. During testing, the pcm uses it to seal the evap system and then observes vacuum decay (bleed to zero). If it doesn't see what it's looking for in a certain amount of time, the pcm sets this code. This indicates that there could be a restriction in the vent side of the evap system, and could be as simple as a plugged vent solenoid, or more difficult like diagnosing an electrical control problem or chasing evap pipes.

A P0440/P0442 code would indicate a fuel cap/evap system leak. You may want to have your code P0446 diagnosed at a shop.

[Bosen_Sweden]

Originally Posted by envoyxuv

A P0440/P0442 code would indicate a fuel cap/evap system leak. You may want to have your code P0446 diagnosed at a shop.

No I don't I want to solve it myself

where kan I find the vent solenoid???

[envoyxuv]

What's the year/make/model/engine?

[Bosen_Sweden]

Chevrolet venture (trans sport) -98 3,4l

[Bosen_Sweden]

I bought the haynes book and started to read. The EVAP Vent valve should be placed near the EVAP canister, but I cant find it... The haynes book also said that on erlier models (pre 1998) the EVAP vent valve dosent exist. On the earlier models there is a pressuresensor beside the Purge valve in the enginecompartment insted.
Maby my7 van is a erlier model.

The VIN: 1GNDX03EXWD133670

I also read somwere that somewhere in the enginecompartment there is a label that tells you more about the EVAP system. Where the hoses are conected and so on... but I can't find the label.

When I blow in the hose from the EVAP canister to the gastank I can build up pressure in the gastank... but when I blow in the hose from the purgevalve into the canister and plug the hose to gastank I can't build up pressure in the canister. It sounds wrong to me but I haven't plug the hose to the tankfill... so maby the pressure goes out that way.

How do a EVAP Canister work??? can I check it in some other way???

Maby I should have sucked in the hose insted???

[Bosen_Sweden]

UPDATE:

The CEL light does not illuminat no more!!!!
I found the EVAP vent valve!!!
I tought that the thick hose from the canister went up to the gas tank filling cap, but I was wrong.... when I folowed the hose I found the EVAP vent valve hidden under some A/C tubes!! I cleaned the EVAP vent valve and tested it with a battery and put it back!!!
Then I connected my OBD2 interface and cleared the DTC... It´s working!!!
I'm Happy!