Evaporative System Small Leak Detected

What it means

During its self-test the computer sealed the evaporative system and watched the pressure, which drifted slowly in a way that indicates a small leak. The leak can be as minor as a worn fuel cap seal.

Symptoms3

• Check engine light with no change in how the car drives.
• Occasional faint fuel smell near the tank.
• No other symptoms in most cases.

Possible causes5

• Cracked or hardened fuel cap seal.
• Hairline crack in an evaporative hose.
• Small leak at the purge or vent valve.
• Leak at a rusted fuel filler neck.
• Minor damage to the charcoal canister.

How to diagnose and fix5

1. Replace the fuel cap if its seal is worn or it is not a proper-fit part.
2. Clear the code and allow several days for the system to retest.
3. Inspect hoses and joints around the canister and tank.
4. Request a smoke test, since small leaks are hard to see.
5. Replace the leaking valve or part once found.

Repair cost

In Saudi riyals; the highlighted part is the expected range for this fault.

Most cases are solved with a new fuel cap or hose at low cost; sometimes a valve or filler neck is needed.

Prices are rough estimates for common cars at independent workshops and vary with the car and the source of the part.

Frequently asked questions