EVAP System Large Leak Detected Fresh Air Side

Common symptoms

What you'll notice

• Inspect and tighten the gas cap to ensure a proper seal.
• Check for any damage or corrosion on the EVAP system hoses and pipes, and repair or replace as necessary.
• Test the purge valve and ensure it is functioning correctly, clean or replace if needed.
• Inspect the EVAP canister for any cracks or leaks, and replace if necessary.
• Perform a smoke test to further locate any potential leaks in the EVAP system and repair accordingly.

Common causes

Most likely first

1. Loose or damaged gas cap
2. Faulty or leaking EVAP canister
3. Cracked or disconnected EVAP hoses
4. Faulty EVAP purge valve
5. Faulty fuel tank pressure sensor

How to diagnose & fix

Work through it in order

1. Check engine light illuminates on the dashboard.
2. Decreased fuel efficiency.
3. Strong fuel smell coming from the vehicle.
4. Difficulty starting the engine.
5. Irregular engine idling or stalling.