Check engine light - Mercedes-Benz Forum

 
LinkBack Thread Tools Display Modes
post #1 of 4 (permalink) Old 10-14-2015, 02:07 PM Thread Starter
BenzWorld Junior Member
 
Date registered: Nov 2012
Posts: 10
Mentioned: 0 Post(s)
Quoted: 0 Post(s)
(Thread Starter)
Check engine light

I have a 2011 C300 with 35000 miles. Recently the check engine light came on on I had it checked and reset. Then three weeks later it has come on again and the code is P0456 and it says evaporative emission system leak detection, very small leak. So not sure if it's the gas tank or not? My car is out of warranty so my question is anyone know what this may be, can I ignore it, any other ideas would be great . I'm not cheap and care for my car well, just not a great time.
Thanks
Todd
mort5029 is offline  
Sponsored Links
Advertisement
 
post #2 of 4 (permalink) Old 10-14-2015, 02:09 PM
BenzWorld Elite
 
oefvetw124lover's Avatar
 
Date registered: Dec 2008
Vehicle: toys: 92 400e,92 300CE & 93 400SEL with daily driver:12 Civic, Workhorse: 15 F150 & Porsche 944
Location: Albany , NY, USA
Posts: 6,077
Mentioned: 3 Post(s)
Quoted: 1057 Post(s)
Garage
Send a message via AIM to oefvetw124lover Send a message via Yahoo to oefvetw124lover
vaporative Emission System Leak Detected (very small leak)
What does this mean?
OBD Code P0456refers to
The Powertrain Control Module (PCM) at different times performs various tests on the EVAP system. OBD II Enhanced EVAP systems are in place to keep fuel tank vapors from venting into the atmosphere, and instead purges them into the engine to be burned. Regular pressure tests are conducted by the PCM to monitor the sealed system for leaks. The PCM monitors the EVAP system pressure by watching the fuel tank pressure (FTP) sensor. When the sensor indicates a small leak in the EVAP system, this code is set.
Symptoms
Possible symptoms of OBD code P0456
There will likely be no noticeable symptoms other than the Malfunction Indicator Lamp (MIL). This is because the EVAP system is a closed system and only controls fuel tank vapors, not engine management.
Causes
Possible causes of OBD code P0456
Usually this P0456 code is caused by an incorrect or faulty gas cap. Filling the fuel tank with the engine running could conceivable cause this code as well or if the cap wasn't properly tightened. Any of the following could also be the cause: A small leak in any of the EVAP hoses or fuel tank hoses A small leak in the purge valve or vent valve The EVAP Canister may be leaking
Possible Solutions
First, using a scan tool activate the vent solenoid, sealing the system. Then monitor the fuel tank pressure (FTP) sensor. If the system is sealing properly, the number will stay consistent. If is isn't, the pressure sensor will show that as well. If the system slowly leaks, use a smoke machine and watch for smoke exiting the system at any EVAP component. Any where there is smoke exiting the system, that is the faulty component. Do not pressurize the EVAP system with air pressure. Doing so can damage the purge and vent solenoids in the system.

Carl


Veteran
Albany, NY, USA

92 300ce and others
"Men sleep peacefully in their beds at night
because rough men stand ready
to do violence on their behalf."

Si vis pacem, para bellum
oefvetw124lover is offline  
post #3 of 4 (permalink) Old 10-14-2015, 02:10 PM
BenzWorld Elite
 
oefvetw124lover's Avatar
 
Date registered: Dec 2008
Vehicle: toys: 92 400e,92 300CE & 93 400SEL with daily driver:12 Civic, Workhorse: 15 F150 & Porsche 944
Location: Albany , NY, USA
Posts: 6,077
Mentioned: 3 Post(s)
Quoted: 1057 Post(s)
Garage
Send a message via AIM to oefvetw124lover Send a message via Yahoo to oefvetw124lover
Usually this P0456 code is caused by an incorrect or faulty gas cap

Usually this P0456 code is caused by an incorrect or faulty gas cap

start with the gas cap before you drive yourself crazy
is it OEM ? does it seal ?

Carl


Veteran
Albany, NY, USA

92 300ce and others
"Men sleep peacefully in their beds at night
because rough men stand ready
to do violence on their behalf."

Si vis pacem, para bellum
oefvetw124lover is offline  
post #4 of 4 (permalink) Old 10-14-2015, 02:16 PM Thread Starter
BenzWorld Junior Member
 
Date registered: Nov 2012
Posts: 10
Mentioned: 0 Post(s)
Quoted: 0 Post(s)
(Thread Starter)
Hello it's the original , should I buy a cheap after market to test then if it corrects buy a OEM.
mort5029 is offline  
Sponsored Links
Advertisement
 
Reply

  Mercedes-Benz Forum > General Mercedes-Benz Forums > General Mercedes-Benz

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Mercedes-Benz Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











  • Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
     
    Thread Tools
    Show Printable Version Show Printable Version
    Email this Page Email this Page
    Display Modes
    Linear Mode Linear Mode



    Posting Rules  
    You may post new threads
    You may post replies
    You may not post attachments
    You may not edit your posts

    BB code is On
    Smilies are On
    [IMG] code is On
    HTML code is Off
    Trackbacks are On
    Pingbacks are On
    Refbacks are On

     

    Title goes here

    close
    video goes here
    description goes here. Read Full Story
    For the best viewing experience please update your browser to Google Chrome