2003 GMC Sonoma Can not fill gas tank and code P0449 is tri

JACKIE SHERRILL

MEMBER
2003 GMC SONOMA
6 CYL
4WD
AUTOMATIC
105,000 MILES

My engine light has been on for a week or so. The other day I was unable to fill my gas tank, it would just bubble out as I added gas (approximately 1/2 gallon). My scanner gave me a P0449 code.

With the ignition on, my test light illuminated at the wiring harness (one side of the harness) at the vent solenoid located on the manifold. The test light also illuminated at the wiring harness for the vent valve back beside the charcoal canister. I replaced the vent valve and vent solenoid and still have the same problem.

The factory service manual says there may be a short to ground for the control circuit of the vent solenoid. I am not sure how to test for that. Also, how can I get power to the solenoid if it is grounded? Can some one help.

Also, what else could it be. I am no expert by any stretch, but it seems like I am getting power everywhere and with a new vent valve and solenoid, I am not sure where else to look.

Any help would be greatly appreciated.

1 Reply

SATURNTECH9

MECHANIC
30,869 POSTS

The solenoid you changed by the intake manifold was probably the canister purge solenoid and has nothing to do with the code or not being able to fill the tank with gas. You need to be concern with the vent solenoid by the charcoal canister. With the key in the on position engine off the orange wire terminal A to the vent solenoid should have battery voltage. Now check terminal B white wire for being grounded it shouldn't be grounded at this point. Let me know what you find.