Go5.3tt06

iTrader: (1)

Wonder if it would help me to see the pictures. Would you please? If you have a chance to take picture. I wamnt to see it.

1FastBrick

iTrader: (17)

Torque Wrench and budhayes3 What are you guys doing about code P0446. I believe it is defined as evap vent performance issuse... I know there is a TSB about it recomending to replace the solinoid and filter with the redisigned vent and filter which is usually what I do. Sometimes I find the the pressure sensor on top of the fuel pump is also defective.


I did one on a 01 Tahoe that came back. I replaced the vent solind assembly and the pressure sensor on the top of the pump. Also the gas cap was leaking prior and failed the pressure test and was replaced for the smog check. I think that was a P0442 or P0440 code

I recomended the fuel pump assembly since the vehical had 200k milles on it but they wouldn't go for it.

I was reading up on how the system works and basically the computer uses the fuel pressure sensor and the fuel level to determine the proper amount of vacume thats
needed to check the systems for leaks.

Any other thoughts on this one??? Some thing else I should Look at if it returns???

Torque_Wrench

iTrader: (13)

99 % of the time, I just replace the Evap Vent Solenoid and Filter Canister for the P0446. You'll find that when you take it off, the defective one will have dirt and maybe some water in it. That's why we are relocating the filter box to the outside of the frame rail or as I do...up around the drivers seat floor board.

Torque_Wrench

iTrader: (13)

Hmmmmm...let me see if this will work. If it won't let me post the pics, then PM me your email address and I'll email them to you. Cool?

This bulletin is being revised to provide an updated picture of the remote filter box and to add an important statement to not replace the EVAP canister. Please discard Corporate Bulletin Number 02-06-04-037E (Section 06 -- Engine/Propulsion System).


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Condition
Some customers whose vehicles are operated in dusty type environments, such as farming or mining off-road type applications, may comment about the illumination of the check engine light, with a DTC of P0446 (Restricted/Blocked EVAP Vent Path) being set.

Cause
Dirt and dust intrusion into the EVAP canister vent hose assembly, resulting in restricted air flow, may cause this condition.

Correction (1999-2007 Classic/Old Style Models)
After following the published SI diagnostics for P0446 and determining that the EVAP canister vent valve is the cause of the MIL light, replace the existing EVAP canister vent valve assembly with a new assembly. This new assembly is a sealed unit that is designed to be vented through a remote filter box. To ensure correct installation, follow the procedures below.

Important: DO NOT replace the EVAP canister assembly for this concern unless it fails the leak test.

1999-2003 Model Year (Use Service Kit P/N 19207762)
Raise the vehicle. Suitably support the vehicle.
Disconnect the EVAP canister vent valve electrical connector, if equipped.
Disengage the two vent valve pipe clips securing the pipe to the underbody. Remove the clips from the underbody and discard.
Disconnect the vent valve pipe at the EVAP canister.
Remove and retain the EVAP canister vent valve bracket mounting bolt.
Remove the complete EVAP canister vent valve assembly with bracket attached and discard.



Important: The new canister vent valve will be installed in a new location, outside of the frame.

Position and secure the new valve assembly to the frame bracket on the outside of the frame using the existing hole and mounting bolt.
Tighten
Tighten the bracket mounting bolt to 12 N·m (106 lb in).

Connect the vent valve pipe to the EVAP canister.
Install the two vent valve pipe clips into the existing underbody holes.
Connect the EVAP canister vent valve electrical connector, if equipped.
Attach bulk 5/8" heater hose to the vent valve port and secure using a clamp. Run a length as needed along the frame rail routing to the area above the transmission.
Cut the hose to determined length and install the supplied filter box. Secure using a clamp.
Remove the transmission support and lower the transmission assembly as necessary to allow for access to the new filter box location.



Secure the filter box to the transmission vent hose just forward of the hose tee-section using a tie strap. DO NOT pinch or restrict the transmission vent hose. The filter box opening should be pointing downward.
Raise the transmission and reinstall the transmission support.
Tie strap the hose as needed along the frame rail in order to keep the hose away from pinch-points and heat sources.
Lower the vehicle.
2004-2007 Model Year (Use Service Kit P/N 19152349)
Raise the vehicle. Suitably support the vehicle.
Disconnect the EVAP canister vent valve electrical connector.
Disconnect the canister pipe from the vent valve.
Push in the retainer and remove the existing canister vent valve from the fuel tank clip or mounting bracket. Discard the old valve.
Cut back the existing canister pipe approximately 51 mm (2 in) to remove the quick connect end.
Crew Cab Short Box Shown Below, Other Configurations Similar




Extended Cab Short Box Shown Below, Other Configurations Similar




Install the new canister vent valve to the fuel tank clip or mounting bracket.
Cut bulk 5/8" heater hose to a length of approximately 76 mm (3 in). Install the hose between the vent valve and the canister pipe and secure using clamps.
Attach bulk 5/8" heater hose to the vent valve port and secure using a clamp. Run a length as needed along the frame rail routing to the area above the transmission.
Cut the hose to determined length and install the supplied filter box. Secure using a clamp.
Remove the transmission support and lower the transmission assembly as necessary to allow for access to the new filter box location.



Secure the filter box to the transmission vent hose just forward of the hose tee-section using a tie strap. DO NOT pinch or restrict the transmission vent hose. The filter box opening should be pointing downward.
Raise the transmission and reinstall the transmission support.
Connect the EVAP canister vent valve electrical connector.
Tie strap the hose as needed along the frame rail in order to keep the hose away from pinch-points and heat sources.
Lower the vehicle.
Correction (2007-2009 New Style Models)
After following the published SI diagnostics for P0446 and determining that the EVAP canister vent valve is the cause of the MIL light, replace the EVAP canister vent valve assembly and relocate the remote filter box. To ensure correct installation, follow the procedures below.

Important: DO NOT replace the EVAP canister assembly for this concern unless it fails the leak test.

Use Service Kit P/N 19207763
Raise the vehicle. Suitably support the vehicle.
Disconnect the EVAP canister vent valve electrical connector.
Disconnect the vent valve pipe quick connect from the canister.
Either cut the existing valve vent pipe and leave the remaining section of pipe in the vehicle or remove along with the valve.
Push in the retainer and remove the existing canister vent valve from the fuel tank clip or mounting bracket.
Cut back the existing canister pipe approximately 51 mm (2 in) and retain the pipe for use with new valve.
Connect the canister pipe quick connect to the canister.
2500 Crew Cab Short Box Shown Below, Other Configurations Similar




1500 Extended Cab Short Box Shown Below, Other Configurations Similar




Install the new canister vent valve to the fuel tank clip or mounting bracket.
Cut bulk 5/8" heater hose to a length of approximately 76 mm (3 in). Install the hose between the vent valve and the canister pipe and secure using clamps.
Attach bulk 5/8" heater hose to the vent valve port and secure using a clamp. Run a length as needed along the frame rail routing to the passenger side area above the transmission.
Cut the hose to determined length and install the supplied filter box. Secure using a clamp.
Remove the transmission heat shield, if necessary.
Remove the transmission support and lower the transmission assembly as necessary to allow for access to the new filter box location.



Secure the filter box to the transmission vent hose just forward of the hose tee-section using a tie strap. DO NOT pinch or restrict the transmission vent hose. The filter box opening should be pointing downward.
Raise the transmission and reinstall the transmission support.
Reinstall the transmission heat shield.
Connect the EVAP canister vent valve electrical connector.
Tie strap the hose as needed along the frame rail in order to keep the hose away from pinch-points and heat sources.
Lower the vehicle.

Torque_Wrench

iTrader: (13)

Well that didn't work...let's try this.

TURBHOE

iTrader: (4)

is this p0449 or 0446? my buddy's 08 yukon xl has a p0449

Torque_Wrench

iTrader: (13)

Hey Mike...it's on it's way.

TURBHOE

iTrader: (4)

thanks bud!! the remote start won't work on these things if there is a CEL.

LOBO2

iTrader: (4)

Is there any updates or new information to be applied when repairing 0446 code? My 2004 Silverado CCSB 5.3L Z-71 is throwing it.

j20owner

Replace vent solenoid and vapor canister along with relocated filter for a p0446.

P0449 is a vent solenoid control circuit fault.