| Subject: | Adm Msg -- P0440 Caused By Gas Cap Not Being Tightened After Fuel Fill |
| Models: | 2002-2003 Chevrolet TrailBlazer |
| 2002-2003 Oldsmobile Bravada |
| Equipped with LL8 4.2L Engine or LM7 5.3L Engine |
| Attention: | Service Manager |
Some customers may comment about a Check Engine light with a P0440 series DTC
indicating that an evaporative emission leak has been detected. After
reviewing the warranty data and making dealer callbacks, General Motors Service Operations
has found that a very high percentage of these DTCs are caused by the gas cap not
being completely tightened after a fuel fill. There is no known issue with gas cap
retention. Therefore, if a dealer should get a vehicle in with this failure, and after
running through the SI diagnosis no other trouble is found, please ensure that the
gas cap is tight. Instruct the customer that this issue may have been caused by the
cap not being tightened after the last fill up. In addition, to ensure that customers
do not experience a similar incident with the first 200 miles of ownership, please
ensure that the technicians performing the PDI or initial tank fill up at your dealership
are tightening the gas cap completely. To make sure the gas cap is secured completely,
you must hear at least 3 clicks.
