OBD-IIEVAP System
EVAP System Fault Codes
Evaporative emission control system leak and valve fault codes.
Diagnostic Approach — EVAP System
- 1
Check fuel cap first — tighten or replace if loose or damaged O-ring.
- 2
Inspect all EVAP hoses for cracks, especially at connection points.
- 3
Use smoke machine to locate leaks — pressurize to 14 inches H2O.
- 4
Test purge valve and vent valve with DVOM and functional test.
- 5
Check charcoal canister for saturation or physical damage.
AI-Guided EVAP System Diagnosis
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