Vehicles With Trouble Code P0496 - keywords 4.8 5.3 6.0 DTC evap L18 L33 L59 L76 LC9 LH6 LMG LM7 LY2 LY5 LY6 LQ4 LQ9 LU3 MIL SES tank
| Subject: | Vehicles With Trouble Code P0496 |
| Models: | 2007 Cadillac Escalade |
| 2006-2007 Cadillac Escalade Classic Body Style |
| 2006-2007 Chevrolet Avalanche, Express, Silverado Classic Body Style |
| 2007 Chevrolet Avalanche, Express, Silverado, Tahoe |
| 2006-2007 GMC Savana, Sierra Classic Body Style |
| 2007 GMC Savana, Sierra, Yukon |
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
A dealer may encounter a customer concern of intermittent trouble code P0496.
Recommendation/Instructions:
Complete the SI diagnostics for any trouble codes or symptoms found. If DTC P0496 only occurs when a vehicle is moved from a cold ambient temperature (parking area), to a shop with a warm ambient temperature, do not attempt repairs.
After 2 hours in a warm shop, the IAT and coolant sensors could have warmed up enough to enable the P0496 diagnostic, but the fuel in the tank may still be cold. When the vehicle is started back up, a large vacuum is created in the tank during the purge valve leak test, and this may falsely set the P0496.
The concern may be worse when the fuel level is high because there is a smaller vapor space, and it's more likely to build a vacuum in the tank.
Engineering is investigating the false setting of P0496, and this PI will be updated when new information becomes available.
Please make Field Product Reports (using bulletin number 02-00-89-002F) on vehicles with the P0496 occurring as listed in this PI.
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.
