Subaru Forester Owners Forum banner

1 - 4 of 4 Posts

·
Registered
2003 Forester XS Premium Auto
Joined
·
14 Posts
Discussion Starter #1
Hi,

I have been getting a P0457 code on my 2003 Forester XS for the past 10 months. I went thru all the procedures I found in the forums including a new gas cap but nothing fixed the issue.

Finally this spring I decided to check the canister vent valve. I had heard that since it is at the lowest point in the system it can accumulate moisture and seize up. This really should have noting to do with the error code but I was getting desperate to correct the issue. So I connected the test wires under the dash and listened for the clicking sound of it opening and closing. No sound. Put a meter to the wires and I was getting power to it.

It seems the unit was shot so I went online to order a new one. Checked Amazon and found this.

Amazon.com: Dorman 911-650 Vapor Canister Vent Valve: Automotive


When I checked the reviews it seems someone else also discovered that replacing this fixed his P0457 code. So I picked one up to try.

Once I got it I installed it and cleared the code. It has been 6 weeks now without the code popping up. I consider it fixed. :woohoo:
 

·
Registered
Joined
·
2 Posts
@Pharoah, I was cruising the forum looking for info on P0457 since I just threw this code in my 05 Forester. I noted that you said in the OP:

"Finally this spring I decided to check the canister vent valve. .......This really should have nothing to do with the error code"

I think that this component's proper behavior is entirely consistent with code P0457. The code basically means that there is a leak in the evap system. This code is the result of a test that the vehicle runs repeatedly under certain operating conditions (fuel level, vehicle speed, etc.). During this test, the vent valve on the canister is closed and a vacuum is drawn on the system. If the vacuum holds, the test passes and the vent valve is re-opened for normal operation. If the test fails, a code is set. A potential root case of the failed test is a leaky vent valve that has not fully closed during the test. This appears to have been your problem.
 

·
Registered
03 Forester XS and I my girl's 04 Outback H6
Joined
·
3 Posts
I've got the same car 03 Forester XS and same error code P0457. I tightened the gas cap which says Subaru on it, P0457 persists after clearing the code. I have a volt meter but I'm unsure as to how to test this valve.

Under the dash? how does that work?

Also is the Vent Valve the same as a Drain Valve?

This Youtube video calls it a Drain valve.
I just want to make sure I'm working on the right part to solve this. Thanks!

 
1 - 4 of 4 Posts
Top