2018 Audi P0440: What It Means & Is It Safe to Drive?
P0440 on the 2018 Audi: Evaporative Emission System Control System Malfunction. Here's what it means, what usually causes it, what repairs typically cost, and whether it's safe to keep driving.
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What this code means
A general fault in the EVAP system—could be a leak, stuck valve, or sensor issue.
Common causes on the 2018 Audi
- Gas cap loose or faulty
- Purge or vent valve stuck
- Charcoal canister or hose leak
Symptoms
- Check Engine Light
Typical fixes
- Replace gas cap
- Test purge/vent valves
- Smoke test EVAP system
Repair cost range
For a 2018 Audi, repairs for P0440 typically fall between $20 and $400, depending on the root cause and labor rates in your area.
Known issues on Audi
Audi P0440 EVAP system large leak is commonly the gas cap or a cracked charcoal canister hose. Use VCDS to activate the leak detection pump and check its operation. Audi's EVAP system uses a leak detection pump (LDP) that can develop an internal diaphragm failure—test the LDP before smoke testing.
Most commonly affected models
A4 B6/B7 2002–2008A6 C6 2005–2011Q7 2007–2015