How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Jerry Newton Your Own Question
Jerry Newton
Jerry Newton, GMC Technician
Category: GM
Satisfied Customers: 4829
Experience:  ASE Master Technician, L1, Master GM Technician. Over 20 years of bumper to bumper GM experience.
25345654
Type Your GM Question Here...
Jerry Newton is online now
A new question is answered every 9 seconds

P0499, Evaporative Vent Solenoid location and diagram

Customer Question

2003 Silverado check engine code: P0499, Evaporative Vent Solenoid location and diagram
Submitted: 7 years ago.
Category: GM
Expert:  Jerry Newton replied 7 years ago.
The vent solenoid is near the gas tank under the bed. Also, the one the dealer gave you doesn't look like the one you have, because it's been redesigned. Did the new part come with installation instructions? They want you to relocate it. I can get those instructions, perhaps, if you need them.
Customer: replied 7 years ago.

Perhaps you are correct, that makes sense that they'd redesign it however, it came with the same exact hose *(or at least it seemed to be identical). I was able to access the OEM valve but couldn't wiggle it out of it's original place. I suppose the gas tank has to be dropped to gain access. Where is it to be relocated? What about the original power connector? Any advice is appreciated.

 

Thanks.

Expert:  Jerry Newton replied 7 years ago.
You are going to take the bolt out of the bracket that the old valve is attached to, and throw the whole thing away. The new valve is going to be mounted outboard of the frame. Hang tight for a few and I'll attach the bulletin here so you can see what you need to do. Gas tank does not need to come out, but you may need to be something of a contortionist.
Expert:  Jerry Newton replied 7 years ago.

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)

  1. Raise the vehicle. Suitably support the vehicle.
  2. Disconnect the EVAP canister vent valve electrical connector, if equipped.
  3. Disengage the two vent valve pipe clips securing the pipe to the underbody. Remove the clips from the underbody and discard.
  4. Disconnect the vent valve pipe at the EVAP canister.
  5. Remove and retain the EVAP canister vent valve bracket mounting bolt.
  6. Remove the complete EVAP canister vent valve assembly with bracket attached and discard.

  7. Object Number:(NNN) NNN-NNNN Size: SH
    Click here for detailed picture of above image.

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

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

  10. Connect the vent valve pipe to the EVAP canister.
  11. Install the two vent valve pipe clips into the existing underbody holes.
  12. Connect the EVAP canister vent valve electrical connector, if equipped.
  13. 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.
  14. Cut the hose to determined length and install the supplied filter box. Secure using a clamp.
  15. Remove the transmission support and lower the transmission assembly as necessary to allow for access to the new filter box location.

  16. Object Number:(NNN) NNN-NNNN Size: SH
    Click here for detailed picture of above image.
  17. 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.
  18. Raise the transmission and reinstall the transmission support.
  19. Tie strap the hose as needed along the frame rail in order to keep the hose away from pinch-points and heat sources.
  20. Lower the vehicle.