p0456
Easy Fix
Audi · SUVs
Evaporative Emission System Leak Detected (Very Small Leak)
Quick Answer
Error code P0456 on your Audi SUVs means: Evaporative Emission System Leak Detected (Very Small Leak). This is usually fixable — see the step-by-step guide below.
Affected Models
Likely Causes
How to Fix It
1
Remove and inspect the fuel cap; replace if the seal is cracked or worn
2
Perform an EVAP smoke test to locate the small leak
3
Inspect all EVAP system hoses and quick-connect fittings
4
Test the purge valve and vent valve for proper sealing using a scan tool
5
Check the EVAP canister and fuel filler neck for cracks
Pro Tip
This is a common issue that most users can resolve without specialized tools. Try the first step before moving on to more complex solutions.
Parts You May Need
Fuel cap
EVAP hoses
Purge valve
EVAP canister
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