Service VME - Evaporative Emission Canister Control Valve Diagnosis - cap code DTC EVAP emissions part P0440

When servicing the vehicle with the VIN you entered, the following diagnosis might be helpful if the vehicle exhibits the described symptoms.

A large number of canister control valves, part number 15750484 returned to the Warranty Parts Return Center were found to be functioning properly. Many of the corresponding repair orders indicated that DTC P0440 was present. As a reminder, the most probable cause of DTC P0440 is that the vehicle has been driven without the fuel cap being securely tightened. Be sure to follow all diagnostic procedures for DTC P0440 outlined in SI document number 653273 which includes the smoke test.

Please follow this diagnosis 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. If these steps do not resolve the condition, please contact GM TAC for further diagnostic assistance. This diagnostic approach was developed for the vehicle with the VIN you entered and should not be automatically be used for other vehicles with similar symptoms.