Diagnostic Aids

Check for following conditions:

• Poor connection at PCM/ECM. Inspect harness connectors for following conditions:
  • Backed-out terminals.
  • Improper mating.
  • Broken locks.
  • Damaged terminals.
  • Poor terminal to wire connection.
• Damaged harness. Inspect wiring harness for damage. If harness appears to be okay, observe Fuel Tank Vacuum Pressure display on scan tool while moving connectors and wiring harnesses related to sensor. A change in display will indicate location of fault.
• Incorrect purge or vacuum source line routing. Verify that source vacuum and purge lines to EVAP emission canister purge valve are not switched.

Fig 1: EVAP Control System Diagnosis (1 Of 3)

Courtesy of DAEWOO

Fig 2: EVAP Control System Diagnosis (2 Of 3)

Courtesy of DAEWOO

Fig 3: EVAP Control System Diagnosis (3 Of 3)

Courtesy of DAEWOO