P0456 — Evaporative Emissions System Small Leak Detected
Category: Powertrain Severity: Low
Updated:
DTC code P0456 means: Evaporative Emissions System Small Leak Detected. It falls under the "Powertrain" category, with an estimated severity of Low. Common causes include loose or faulty fuel cap, very small EVAP leak and faulty purge/vent valve; it's worth confirming the diagnosis before replacing parts.
Possible causes
- Loose or faulty fuel cap
- Very small EVAP leak
- Faulty purge/vent valve
Symptoms
- Check engine light
- Fuel smell
- No driving symptoms
How to diagnose it step by step
- Check and tighten the cap.
- Replace the cap if the seal is cracked.
- If it returns, smoke-test the EVAP system.
How to fix it
Check the fuel cap and the EVAP system hoses and valves.
Estimated repair cost
Cap: $10–40. Smoke test: $50–150.
Frequently asked questions
What does DTC code P0456 mean?
Evaporative Emissions System Small Leak Detected.
Is code P0456 serious?
Severity Low. Usually a minor fault; check the causes listed.
Can I keep driving with code P0456?
Yes, no risk.
Related codes
P0455 P0457 P0453 P0452 P0449 P0447 P0446 P0443 P0442 P0441
Refine by car make
- Audi P0456: Very small EVAP leak.
- BMW P0456: Fuel cap or very small leak.
- Citroën P0456: Fuel cap or canister.
- Fiat P0456: Fuel cap or purge valve.
- Ford P0456: Fuel cap or very small leak.
- Honda P0456: Loose fuel cap.
- Opel P0456: Fuel cap or very small leak.
- Peugeot P0456: Fuel cap or very small leak.
- Renault P0456: Fuel cap or very small leak.
- Toyota P0456: Loose fuel cap.
- Volkswagen P0456: Very small EVAP leak.
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