Diagnostic Procedures
- Perform On-Board Diagnostic (OBD) system check. See ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK under SELF-DIAGNOSTIC SYSTEM. After performing OBD system check, go to next step.
- Turn ignition on, with engine off. Using scan tool, review Freeze Frame/Failure records. If DTC P0452, P0453 or P1640 is set, diagnose affected DTC(s) first, then retest system. If DTC P0452, P0453 or P1640 is not set, go to next step.
- Start engine. Using scan tool, command EVAP system seal on. Hold engine speed at 2000 RPM. Monitor fuel tank pressure. If fuel tank pressure increases to greater than 2 volts, replace EVAP purge solenoid. If fuel tank pressure does not increase to greater than 2 volts, problem is intermittent. See DIAGNOSTIC AIDS .