SES MIL Evap DTC And/Or Hard To Fill - keywords emission engine evap evaporative fuel large leak P0446 P0442 P0455 pressure purge solenoid tank vacuum vent
| Subject: | SES MIL Evap DTC And/Or Hard To Fill |
| Models: | 2007-2009 Cadillac Escalade, ESV, EXT |
| 2007-2009 Chevrolet Avalanche, Suburban, Tahoe |
| 2007-2009 GMC Yukon, Yukon XL, Yukon Denali, Yukon Denali XL |
This PI was superseded to update model years and provide external fix. Please discard PIT4347E.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
Some owners may comment that the SES is illuminated and when checking for DTCs the ECM will have set an Evap DTC. While performing normal diagnostics it may be noticed there is excessive moisture/water/corrosion at the vent valve solenoid, vent valve pipes, and/or EVAP canister. The vent valve solenoid draws fresh air from near the top of the fuel filler pipe. In some situations, it is possible that water spray from the rear wheels may be drawn in though the vent valve pipe at the top of the fuel filler pipe.
Recommendation/Instructions:
GM engineering is aware of this concern and working on a GM service kit to correct this concern. In the mean time, the kit can be made from readily available parts and using the following procedure below:
Parts List
Part number | Description | Qty |
|---|---|---|
15844701 | evap vent inlet hose ¾" Heater Hose | 1 |
¾" Heater Hose | 2.5" (6.3cm) | |
98755K24 | Inlet Screen | 1 (obtain from McMaster Carr Supply 1-330-995-5500) |
8650K112 | Acrylic/PVC sheet material | 1 (obtain from McMaster Carr Supply 1-330-995-5500) |
Zip Ties | As needed |
- Remove the existing vent hose "mushroom cap" (2) and zip ties (1), as shown below.
- Add 31" (79mm) to existing snorkel hose using a length of hose taken from P/N 15844701. Join hose sections together with a 2.5" length of ¾" heater hose, as shown below.
- Slide inlet screen (98755K24) over the end of the new hose section.
- Remove Fuel Filler "Sugar Scoop" from vehicle.
- Add holes to "Sugar scoop" to retain inlet hose, as shown below.
- Fabricate splash shield from Acrylic/PVC sheet material (8650K112), as shown below.
- 1. 6.645 inches wide
- Attach end of vent hose and screen with zip tie as shown and reassembly with fabricated splash shield between "sugar scoop" and fuel filler pipe, as shown.
- Route new vent hose along fuel filler pipe and add necessary zip tie to retain hose.
2. 9.75 inches long
3. Use filler "sugar scoop" as template to locate one large hole for fill neck and 3 small holes for mounting screws.
4. 45 degree cut 1.25" in from corner on each side as shown
5. Use a quart can to mark radius on two corners
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
