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post #1 of 3 (permalink) Old 04-14-2013, 05:52 PM Thread Starter
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Question P0449

Hi everyone. I recently had the check engine light come on and when I scanned it, it gave me the P0449 code. I noticed that there hasn't been the usual tapping sound from the trunk after starting the car, so I replaced both the evap canister solenoid valve and the purge solenoid valve, but the code is still appearing. I finally checked the voltage at the evap canister vent solenoid and I was getting 2.8-2.9 volts while the car was running, which doens't seem normal. Any ideas or suggestions are greatly appreciated.
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post #2 of 3 (permalink) Old 04-14-2013, 06:00 PM
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Conditions for Running the DTC•The ignition is ON.
•The system voltage is between 9–18 volts.
•DTCs P0443 and P0449 run continuously when the above conditions are met.

---------- Post added at 08:00 PM ---------- Previous post was at 07:57 PM ----------

P0449
 1. Ignition OFF, disconnect the harness connector at the EVAP canister vent solenoid valve.
 2. Ignition ON, verify that a test lamp illuminates between the voltage supply circuit terminal A and ground.
⇒ If a test lamp does not illuminate, test the voltage supply circuit for a short to ground or an open/high resistance. If the circuit tests normal and the voltage supply circuit fuse is open, test or replace the EVAP canister vent solenoid valve.
 3. Connect a test lamp between the voltage supply circuit terminal A and the control circuit terminal B.
 4. Command the solenoid ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between commanded states.
⇒ If the test lamp is always ON, test the control circuit for a short to round. If the circuit tests normal, replace the control module.
⇒ If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the control module.
 5. If all circuits test normal, replace the EVAP canister vent solenoid valve.
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post #3 of 3 (permalink) Old 04-20-2013, 05:14 PM Thread Starter
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I tested the new and old vent solenoids by connecting them to a 12 volt battery and found that all of them worked. But I noticed that when I plugged the EVAP canister vent solenoid back into the connector but not back into the Evap canister and watched it as I started the car with my remote starter, it didn't move or anything, I was still getting 2.8 volts at the plug. Im suspecting that the cause is electrical. Any ideas?

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cel , evap , p0449 , solenoid , vent valve

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