2020 Mercedes-Benz P0455: What It Means & Is It Safe to Drive?
P0455 on the 2020 Mercedes-Benz: Evaporative Emission System Leak Detected (Large Leak). 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 large leak has been detected in the EVAP system. Could be gas cap left off, disconnected hose, or damaged canister.
Common causes on the 2020 Mercedes-Benz
- Gas cap missing or not sealed
- Disconnected or ruptured EVAP hose
- Damaged charcoal canister
- Faulty purge/vent solenoid
Symptoms
- Check Engine Light
- Fuel smell possible
Typical fixes
- Install or replace gas cap
- Inspect and repair EVAP hoses
- Replace canister or valves as needed
Repair cost range
For a 2020 Mercedes-Benz, repairs for P0455 typically fall between $20 and $500, depending on the root cause and labor rates in your area.
Known issues on Mercedes-Benz
Mercedes P0455 is frequently caused by a cracked Pierburg purge valve diaphragm. After confirming the gas cap seals correctly, replace the purge valve before performing a smoke test—it is the single most common P0455 cause on W204, W211, and W212 platforms.
Most commonly affected models
C-Class 2008–2014E-Class 2003–2009ML-Class 2006–2011