That's a code for large leak in the evap system I have seen the canister purge solenoid's stick open causing that code there supposed to closed and then the computer open's it to allow vacuum to the gas tank to check the system for leak's. When they stick open it creates leak's. Here is what it say's about that code.
* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. See: Verification Tests and Procedures
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions provides an overview of each of the diagnostic category.
* Evaporative Emission (EVAP) System Large Leak
The control module tests the evaporative emission (EVAP) system for a large leak. The control module monitors the fuel tank pressure (FTP) sensor signal to determine the EVAP system vacuum level. When the conditions for running are met, the control module commands the EVAP canister purge solenoid valve OPEN and the EVAP vent solenoid valve CLOSED. This allows engine vacuum to enter the EVAP system. At a calibrated time, or vacuum level, the control module commands the EVAP canister purge solenoid valve closed, sealing the system, and monitors the FTP sensor input in order to determine the EVAP system vacuum level. The following table illustrates the relationship between the ON and OFF states, and the OPEN or CLOSED states of the EVAP canister purge and vent solenoid valves.
Wednesday, December 8th, 2010 AT 10:21 PM