Emissions

2008 CHEVROLET SILVERADO
120,000 MILES • 5.3L • V8 • 4WD • AUTOMATIC
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CHASEP1275565
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Vent valve high circuit code p0446. replaced vent valve fixed for about a month. Now it is throwing the same code. When you open the gas cap it sucks in air and you can hear a thumping noise within the gas tank. What could be the issue?
Feb 4, 2017 at 8:06 AM
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SATURNTECH9
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Where was the valve you replaced located ?
Feb 4, 2017 at 11:23 PM
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CHASEP1275565
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In the rear of the vehicle.
Feb 5, 2017 at 8:34 AM
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SATURNTECH9
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Sounds like there is a hose blocked or pinched somewhere or the new vent valve is stuck shut.Can you blow thru the new vent valve?
Feb 6, 2017 at 10:59 PM
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CHASEP1275565
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Yes
Feb 9, 2017 at 1:24 AM
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SATURNTECH9
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The vent hose on the vent valve is clear as well?
Feb 9, 2017 at 5:03 AM
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CHASEP1275565
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Replaced those hoses too
Feb 9, 2017 at 11:49 AM
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SATURNTECH9
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Your still have the lot of air rushing when removing the cap after replacing all that?
Feb 9, 2017 at 12:17 PM
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CHASEP1275565
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Yeah I do
Feb 11, 2017 at 4:49 AM
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SATURNTECH9
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Then your tank still isn't venting are you still setting the same code as well?
Feb 11, 2017 at 6:39 AM
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CHASEP1275565
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Yep same things happening
Feb 21, 2017 at 11:03 AM
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CHASEP1275565
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Same code
Feb 21, 2017 at 11:04 AM
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SATURNTECH9
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With the key in the run position unplug and plug the vent valve a couple of times does the vent valve click each time it's plugged and unplugged?
Feb 22, 2017 at 10:43 PM
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