p0456
Easy Fix
Audi · Sedans
Evaporative Emission System Leak Detected (Very Small Leak)
Quick Answer
Error code P0456 on your Audi Sedans 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
Inspect the fuel cap for cracks and ensure it clicks when tightened
2
Perform a smoke test on the EVAP system to locate the small leak
3
Inspect all EVAP hoses and connections for cracks or loose fittings
4
Test the purge valve and vent valve for proper sealing
5
Check the EVAP canister for damage or saturation
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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