P0455 on Mercedes-Benz C-Class: Symptoms, Causes & DIY Fix
Official technical diagnostic wire for fault code P0455 (P0455: Evaporative Emission Control System Leak Detected (Gross Leak)) specifically affecting Mercedes-Benz C-Class vehicles equipped with 2.0L Turbo 4-Cyl with 48V Mild Hybrid (M254 255HP) / AMG C 43 (402HP).
1. Symptoms of P0455 on Mercedes-Benz C-Class
When the Engine Control Module (ECM/PCM) on your Mercedes-Benz C-Class (2.0L Turbo 4-Cyl with 48V Mild Hybrid (M254 255HP) / AMG C 43 (402HP)) logs fault code P0455, drivers commonly observe:
2. Most Likely Causes on Mercedes-Benz C-Class
Historical warranty claims and technical repair bulletins for Mercedes-Benz C-Class point to the following failure distribution:
3. Step-by-Step DIY Repair Guide for Mercedes-Benz C-Class
Remove gas cap, inspect rubber O-ring for cracks, tighten until it clicks 3 times. on the Mercedes-Benz C-Class equipped with 2.0L Turbo 4-Cyl with 48V Mild Hybrid (M254 255HP) / AMG C 43 (402HP).
If the cap rubber is dried or cracked, replace with genuine OEM cap ($15). on the Mercedes-Benz C-Class equipped with 2.0L Turbo 4-Cyl with 48V Mild Hybrid (M254 255HP) / AMG C 43 (402HP).
Disconnect electrical plug and vacuum hose. Apply 12V; verify valve seals tight when unpowered. on the Mercedes-Benz C-Class equipped with 2.0L Turbo 4-Cyl with 48V Mild Hybrid (M254 255HP) / AMG C 43 (402HP).
Check vent valve for road salt corrosion or spider nest clogs. on the Mercedes-Benz C-Class equipped with 2.0L Turbo 4-Cyl with 48V Mild Hybrid (M254 255HP) / AMG C 43 (402HP).
Pump mineral oil smoke into EVAP port to reveal any hairline cracked lines. on the Mercedes-Benz C-Class equipped with 2.0L Turbo 4-Cyl with 48V Mild Hybrid (M254 255HP) / AMG C 43 (402HP).
4. Mercedes-Benz C-Class P0455 FAQs
What causes code P0455 to trigger on a Mercedes-Benz C-Class?
On the Mercedes-Benz C-Class (2.0L Turbo 4-Cyl with 48V Mild Hybrid (M254 255HP) / AMG C 43 (402HP)), P0455 is most frequently caused by Missing, loose, or cracked gas cap seal or Faulty EVAP purge control solenoid. Factory sensor degradation or wiring harness wear near the engine bay are common factors.
Can I safely drive my Mercedes-Benz C-Class with code P0455?
Yes. Completely safe to drive, but emissions test will fail. Given that P0455 carries a Low severity rating on Mercedes-Benz vehicles, we advise performing diagnostic scanning via the OBD-II port located under driver dash beneath purple/black sliding protective door before extended highway driving.
Where is the diagnostic port located on the Mercedes-Benz C-Class?
The 16-pin OBD-II DLC connector on the Mercedes-Benz C-Class is situated under driver dash beneath purple/black sliding protective door. It requires no special tools to plug in a standard scanner.
How much does it cost to fix P0455 on a Mercedes-Benz C-Class?
DIY replacement parts typically range between $15 - $250 (DIY: $15 - $50). If serviced at an authorized Mercedes-Benz dealership, expect an additional $120–$250 in professional labor based on their $185/hr hourly rate.