Emission code is p0449?

2002 GMC SIERRA
220,000 MILES • 5.3L • V8 • 4WD • AUTOMATIC
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SPIRITWOOD
A rubber hose approx 1/4 inner diameter dropped about a foot down under truck. Tracking the hose it splits over transmission attaching to small metal pipe mounted near the top to the bell housing. The hose other part of split went up to engine block where it had what looked like a plug or check valve? Ending with no further connection at the engine. I could not find anywhere to mount the hanging part of the hose. The only code is p0449 but all of the lines from the rear are intact. Can’t find any diagrams for this line.
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Aug 24, 2025 at 2:29 PM
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STRAILER
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They items in the images are vents meant to off gas the transmission and transferase. They are used for differentials as well. The code is for the EVAP system.

P0449 - EVAP System Vent Valve/Solenoid Control Circuit Malfunction

So the vent valve will go out near the rear of the tank, check for tears or holes in the EVAP hoses while you are back there. Clear the codes once the repair are made. Check out the images (below). Please let us know what happens.
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Aug 24, 2025 at 5:14 PM
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SPIRITWOOD
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I checked the evap in rear when I got the code, but wanted to figure out the hanging hose before I went past the initial search for damage.so the hose does not connect to anything else? I had my fuel pump and o2 sensors replaced two years ago so I’ll be checking everything again. Thanks
Aug 24, 2025 at 5:34 PM
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STRAILER
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No, the vent hose it suppose to be mounted up high to help keep water out. You can use a smoke machine to help find the leak if there is one, here is a video of the machine being used.

https://www.youtube.com/watch?v=LRKWV4Are5c

Let us know how it goes.
Aug 25, 2025 at 9:12 AM
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SPIRITWOOD
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Replaced evaporator vent solenoid and the evaporator vent purge solenoid no more codes
Aug 28, 2025 at 1:27 PM
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STRAILER
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Nice work, I am happy when we can fix um! Have a great weekend! Can you please leave us a rating?

https://g.page/r/CZdEnyCkGgm6EB0/review

and

https://www.sitejabber.com/reviews/2carpros.com

Thank you! :)
Aug 29, 2025 at 11:42 AM
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