Engine-CodesMercedes-Benz – P0455 Mercedes-Benz

P0455 Mercedes-Benz Code - Evaporative Emission Control System Leak Detected Gross Leak

Quick Answer

The P0455 code for Mercedes-Benz indicates that there is a gross leak detected in the Evaporative Emission Control System. Common causes include Loose or damaged gas cap, Cracked or disconnected hoses, Faulty purge valve. Severity is Low - monitor the vehicle and repair when practical. The vehicle can usually be driven if no severe symptoms are present, but symptoms should be checked before extended driving.

What it means
P0455 Mercedes-Benz indicates Evaporative Emission Control System Leak Detected Gross Leak.
Common causes
Common causes include Loose or damaged gas cap, Cracked or disconnected hoses, Faulty purge valve.
Severity
Low - monitor the vehicle and repair when practical.
Can I drive?
The vehicle can usually be driven if no severe symptoms are present, but symptoms should be checked before extended driving.
Table of contents Created and updated by William Orellana on Sep 07, 2024
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Code P0455 Mercedes-Benz Description

The P0455 code for Mercedes-Benz indicates that there is a gross leak detected in the Evaporative Emission Control System. This system is designed to prevent harmful fuel vapors from escaping into the atmosphere by storing and then burning them in the engine. A gross leak means that there is a significant issue with the system, allowing a large amount of fuel vapor to escape.

OBDII Code P0455 Mercedes-Benz - Evaporative Emission Control System Leak Detected Gross Leak
P0455 Mercedes-Benz Code - Evaporative Emission Control System Leak Detected Gross Leak

Common Causes of P0455 Mercedes-Benz

  1. Loose or damaged gas cap
  2. Cracked or disconnected hoses
  3. Faulty purge valve
  4. Damaged charcoal canister
  5. Leaking fuel tank

Symptoms of P0455 Mercedes-Benz

  1. Decreased fuel efficiency
  2. Difficulty starting or stalling
  3. Check engine light illuminated
  4. Strong fuel odor
  5. Hissing sound near the fuel tank

How to Fix P0455 Mercedes-Benz

  1. Inspect the gas cap for proper sealing and tighten or replace if necessary.
  2. Check all hoses in the Evaporative Emission Control System for cracks or disconnections and repair or replace as needed.
  3. Test the purge valve for proper operation and replace if faulty.
  4. Inspect the charcoal canister for damage and replace if necessary.
  5. Pressure test the fuel tank to detect any leaks and repair as needed.

Cost to Fix P0455 Mercedes-Benz

The typical repair costs for addressing a P0455 code on a Mercedes-Benz can vary depending on the specific cause of the issue. In general, parts for this repair can range from $100 to $500, with labor costs adding an additional $100 to $300. Overall, the total cost for resolving this issue can range from $200 to $800. However, it's important to keep in mind that these estimates are rough averages, and actual costs may vary based on factors such as location, vehicle make and model, and the extent of the repairs needed. It's recommended to consult with a qualified mechanic or dealership for a more precise cost estimate.

Tech Notes for P0455 Mercedes-Benz

The P0455 it’s a very common code, because the code is set if the gas cap is loose or missing. Start by tighten the gas cap and clearing the code. In most cases the code can be clear by disconnecting the car battery for about 30 minutes.

When is the Code Detected?

Evaporative Emission System (EVAP) control system has a very large leak such as fuel filler cap fell off, EVAP control system does not operate properly.

Need more information about the P0455 Mercedes-Benz code?

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About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P0455 Mercedes-Benz Code

1. What does the OBDII code P0455 on my Mercedes-Benz indicate?

The code P0455 indicates that the Evaporative Emission Control System has detected a gross leak.

2. What are the common symptoms of a P0455 code in a Mercedes-Benz?

Common symptoms may include a strong fuel odor, the Check Engine Light illuminating, and potentially lower fuel efficiency.

3. What are some possible causes of a P0455 code on a Mercedes-Benz?

Potential causes include a loose or damaged gas cap, a leak in the EVAP system, cracked or disconnected hoses, or a faulty EVAP canister.

4. How serious is a P0455 code on a Mercedes-Benz?

While the vehicle may still be drivable with this code, it is important to address it promptly to prevent potential fuel system issues and ensure proper emission control.

5. How can I diagnose a P0455 code on my Mercedes-Benz?

Diagnosis typically involves checking the gas cap for tightness, inspecting EVAP system components for visible damage or leaks, and using a smoke machine to pinpoint the source of the leak.

6. Can I repair a P0455 code on my Mercedes-Benz myself?

Repairing a P0455 code may require locating and fixing the leak in the EVAP system, which can be challenging without proper tools and expertise. It may be best to consult a professional mechanic.

7. How much does it cost to fix a P0455 code on a Mercedes-Benz?

The cost of fixing a P0455 code can vary depending on the specific issue causing the leak and the labor rates of the repair shop. It is recommended to get multiple quotes for comparison.

8. Can a P0455 code on a Mercedes-Benz cause emissions test failure?

Yes, a P0455 code can cause your Mercedes-Benz to fail emissions testing, as it indicates a problem with the vehicle's evaporative emission control system.

9. Is it safe to continue driving my Mercedes-Benz with a P0455 code?

While the vehicle may still be safe to drive, it is important to address the underlying issue causing the code to prevent potential fuel system problems and ensure proper emission control.

10. How can I prevent a P0455 code from appearing on my Mercedes-Benz?

To prevent a P0455 code, make sure to tighten the gas cap properly after refueling, perform regular maintenance checks on the EVAP system, and address any warning lights or symptoms promptly.

Discuss the causes and fixes for P0455 Mercedes-Benz OBDII Code

  • Hey I I changed the purge valve an the hoping the check engine would of turned of but it didn't

  • What model and year is your Mercedes-Benz?

  • Nvm I rested my car by unplugging the battery an passed smog

  • I have a 06 ml350. I have this code P0455 and after SUV is warm and shut off wont start aging. Is this part of that code?? I took vehicle to Mercedes Benz Masano..... they change computer and charge me lots of money still have problem.....

  • It's possible (if on the hoses of the EVAP system is disconnected and and there is a large intake leak) , but not likely. Are there any other codes? Do you have to wait until the engine is cod to start again?

  • Yes! I have to wait until is cold again sometimes till next day

  • no other codes

  • I have a 99 E430 I have changed the gas cap. And my purge valve is ticking as a percaution i cleaned it with some MAF cleaner. The check engine light is still on. Im guessing the next thing is to check the charcoal cannister. Is there any way to clean it or fix it without replacement.

  • Aloha I have a 98 Mercedes e 320 , my cap was twisted in a way where the plastic and metal didn't align so it was on partially for a while ,then it wouldn't start ,put on the comp P0455 ,so I fixed the cap and reset comp started right up several time drove to town wouldn't start , try comp again ,4 or 5 times it started made it half way home just turned off in mid drive tow number 2 my system is closed now good cap , I will try battery off for 30 minutes to reset ,does any body else have any advice on what to next, Mahalo for your aloha g

  • R. ???????

  • Check the crank sensor I had the same issue. Also if the vehicle shuts off while driving.

  • I have a
    1997 Mercedes Benz S420 with 75K miles. In 2015 I had my first Check Engine Light
    experience. . P0455 error code. This was new to me since I owned this mint Benz
    for a short time.

    Replaced
    the Gas tank cap and was on my way for a trouble free driving experience. So I
    thought. In 2016 same scenario. In April of 2017 another surprise so I
    replaced it with a new OEM cap. I purchase a diagnostic scanner for my own use.
    Suddenly the Check engine light came on again. A new item came up. Low Fuel
    flashing. This happened so often, regardless how much fuel was in the tank,
    including a new full tank. It would happen at random and many times sitting at
    a light or stop sign I thought I had the solution. Replace the fuel tank sending unit. The new unit seemed to be more
    accurate but it didn't solve the issue. I never thought to return to basics.
    Replace the cap again. I was chasing my tale along with my very competent
    mechanic. I was looking to finding a leak in the evap system or replacing many
    items

    But no it couldn't be the cap again. The cap
    purchased in April was still under warranty. My vendor had one in stock. I
    drove to pick it up. I immediately installed it but before I drove away cleared
    the code. I drove home, a distance of about 40 miles.

    Iconnected the scanner and to my surprise the P0455 code had disappeared.
    Keeping in mind h ow many times I erased the code and each time the code was
    still there. I did not want to believe
    that the cap purchased in April was
    again the culprit. Time will tell.

  • Do not refuel your ride with engine running!