2017 Mercedes-Benz P0440: What It Means & Is It Safe to Drive?
P0440 on the 2017 Mercedes-Benz: 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 2017 Mercedes-Benz
- 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 2017 Mercedes-Benz, repairs for P0440 typically fall between $20 and $400, depending on the root cause and labor rates in your area.
Known issues on Mercedes-Benz
Mercedes P0440 EVAP leak is often the gas cap or a cracked activated charcoal canister hose. Mercedes EVAP systems require the correct OEM cap specification—aftermarket caps frequently cause false P0440 codes. Use XENTRY/DAS diagnostics to activate the leak detection test before smoke testing.
Most commonly affected models
C-Class W203 2001–2007E-Class W211 2003–2009ML-Class W164 2006–2011