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06 X 2.5, Evap codes struggle p1400, 1420, 0448

1916 Views 2 Replies 2 Participants Last post by  jgal
Hi everyone,

I've been pouring over the forums and have found and fixed a few things, but still getting codes.

Started off with an 0457, changed the filler neck and fixed the corroded wires going to the solenoid sensor on the charcoal canister, also changed that sensor/solenoid (drain valve?) as the pins were corroded. wires showed 13 V. so power was flowing.

Drove for a day with no codes, unfortunately it was the weekend and could not get to e test center.

Next morning codes p1400 and 0447 popped up.

I've since switched out the fuel fuel tank pressure solenoid which sits about the evap canister, and checked all wires, these wires also showed 13V on multi meter, so again power is there.

drove for a bit, sometimes codes come on at 60-100 km, sometimes right away when car is turned on. then p1420 p1400 and p0448 came on.

So i have had:

Fuel tank pressure control solenoid, short, high and low output
evap emission system vent shorted

Does the 13V instead of 12V indicate anything? (or is it my cheap multimeter, or that i use wires to extend the mutli meter to get into the connectors because probes are too fat?

Tonight I plan to pull up some interior and check any wiring or harnesses I find to the ECU and find and use the green connector to check if those two solenoids make noise.. Should i be able to hear something from the one in the canister and the on above it?

Could it be ECU? how do I check it?

If i use the multimeter on the connectors on the solenoid part, does the resitance or lack of tell me if the solenoid is working?

If anyone else has had this problem or can help it would helpful. Starting to get frustrated. lol

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Check the operation of the purge solenoid, normally closed and the vent solenoid, normally open. Then check the rubber tube between them.
So I ordered a power probe, and plan to test the drain valve and the pressure control solenoid with it, I tried connecting the green tester connector under the drivers side dash, but with fuel pump and everything going off could not tell if the drain valve and pressure solenoid were actually working.

I did find something interesting, there is a wire that is soldered into the charcoal canister drain valve wiring and it runs all the way to the ecm where it is soldered into another wire.

I followed this post on nasioc to repair my corroded wires to the charcoal canister.

the 1st and 2nd pic at position 3 (from above post) below shows where 2 yellow green wires are, these get soldered together, and then to the connector on the evap canister. Also from this post, it indicates the second yellow green provides power to the fuel tank pressure solenoid.

I did not see that 2nd green yellow wire when i stripped back the wiring harness on my car.

On my car previous owner or mechanic has put a red/black wire that was connected here (at wires to connector on evap canister) and runs as I mentioned to the wiring harness at the ECM where it is soldered into another wire (3rd/ pic shows the black red wire going into wires at evap canister, 4th pic at ecm harness)

Anyone know why they may have placed that wire? should my 06 Forester have the second green yellow wire from this connection to the tank pressure solenoid?

I also pulled up back passenger side seat to see wiring harness under there and everything looks good, no corrosion, etc.

So planning to bench test drain valve and fuel tank pressure solenoid with power probe, also thinking of disabling/removing the added red/black wire to see what happens. a

Thanks again.

let me know if you have any other thoughts


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