Question about Mercedes-Benz Cars & Trucks
Posted by Anonymous on
a 6ya expert can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of.(from cars to computers, handyman, and even drones)
click here to download the app (for users in the US for now) and get all the help you need.
Posted on Jan 02, 2017
Usually the source of the leak is the gas cap (either loose or defective) but if that doesn't apply to your issue then the canister is next to the gas tank.
Posted on Jun 09, 2009
check gas cap and make sure on good, if possible find another one to try on car to see if that works clear codes before trying(take neg cable off battery for approx ten minute) or might have leak in vaccume line or canister
Posted on Sep 03, 2009
check ur gas cap for tight and proper seal that is the most common problem for the the evap codes if cap is good check fuel and vent lines for damage or leaks from gas cap under vehicle up to engine compartment
Posted on Oct 18, 2009
The best way to find these leaks in these systems now adays, is to take it somewhere that does smoke tests. What they do is inject smoke into the system and if there is any little leak the smoke will come out of it pin pointing the leak. There might be a pin hole in one of the vaccum lines, or the plastic casing on top of the evaporative purge valve could be cracked. The smoke test will find it.
Posted on Mar 30, 2010
OBD II Code P0442
Evaporative System Malfunction, Small Leak
Our emissions expert has put together the following information about
the P0442 fault code. We have also included diagnostic procedures you
can take to your repair shop if the mechanic is having difficulty
analyzing the code.
Related Information Check Engine Light
Emission Gas Definitions
OBD II Fault Code
The evaporative control (EVAP) system captures any raw fuel evaporating from the fuel storage system (e.g. the fuel tank, filler neck, and fuel cap). Under precise operating conditions-dictated by engine temperature, speed, and load-the EVAP system stores and purges these captured fuel vapors back into the combustion process.
Want to Learn More?
The EVAP system is designed not only to capture, store, and purge any raw fuel vapors that leak from areas in the Fuel Storage system, but also to run a series of self-tests that confirm or deny the operational and vapor holding ability of the system. This is an important task because at least 20 percent of vehicle-produced air pollution originates from malfunctioning Vehicle Fuel Storage systems.
There are many ways to "leak test" the EVAP system, but most perform the leak test when the vehicle is sitting (like over night) or during the initial start-up after the vehicle has been sitting over night. The EVAP system's operational performance is also tracked by the Power Train Computer by reading the change in the oxygen sensor voltages and short term fuel trim whenever the stored vapors are released or "purged" back into the combustion process. These values should indicate that fuel is being added to the system and that the overall mixture is getting richer. The purging process occurs when the vehicle is under acceleration, which is when most vehicles require additional fuel.
P0442 Diagnostic Theory for Shops and Technicians
The P0442 code indicates that there is a small leak in the EVAP system, but this is somewhat misleading. What the code really indicates is that the EVAP system will not hold a specified level of vacuum for a specified amount of time when it performs its leak test.
Here is how the evaporative leak test is performed by the Power Train Computer:
Posted on Nov 27, 2010
Tips for a great answer:
Oct 16, 2016 | 2000 Ford Escort
Oct 14, 2016 | Cars & Trucks
Mar 15, 2015 | Cars & Trucks
Jul 11, 2014 | Mazda Cars & Trucks
Dec 07, 2013 | Cars & Trucks
Sep 10, 2012 | 2005 Mercedes-Benz C-Class
May 21, 2011 | Toyota Highlander Cars & Trucks
P0305....Cylinder 5 Misfire Detected
P0442....Evaporative Emission Control System Leak Detected (small leak)
P0455....Evaporative Emission Control System Leak Detected (gross leak)
Feb 11, 2011 | 2001 Dodge Caravan
Aug 13, 2010 | 2003 Saturn VUE
Aug 06, 2010 | 1996 GMC Jimmy
Dec 10, 2017 | Mercedes-Benz E-Class Cars & Trucks
43 people viewed this question
Usually answered in minutes!
Step 2: Please assign your manual to a product: