P0442 Evaporative Emission Control System Leak Detected (small leak)
OBD-II Trouble Code Technical Description
Evaporative Emission Control System Leak Detected (small leak)
What does that mean?
This diagnostic trouble code (DTC) is a generic powertrain code, which means that it applies to many OBD-II equipped vehicles. Although generic, the specific repair steps may vary depending on make/model. This code is found on many makes including but not limited to Ford, GMC, Jeep, Dodage, Toyota, BMW, Chrysler, Subaru, etc.
The vehicle’s PCM (powertrain control module) tests the evaporative emissions (EVAP) system for large and small leaks among other conditions. In the case of this DTC, it indicates a fuel vapor leak in the EVAP control system. It means a very small leak has been detected. In fact, the leak can be from a hole as small as 0.04" in diameter. The (EVAP) emission control system prevents the escape of fuel vapors from a vehicle’s fuel system.
Fuel vapors are routed by hoses to a charcoal canister for storage. Later, when the engine is running a purge control valve opens allowing intake vacuum to siphon the fuel vapors into the engine to be burned. That results in decreased vehicle emissions.
Photo of a typical gas cap:
Symptoms
The only thing you will notice is the Malfunction Indicator Lamp (MIL) a.k.a. Check Engine Light will be illuminated. You likely won’t notice any drivability problems although sometimes a fuel odor may be noticed.
Causes
A code P0442 most likely means one or more of the following has happened:
Possible Solutions
With a P0442, the most common DIY repair is to:
More advanced troubleshooting steps include:
Generally there are vehicle and model specific procedures for proper diagnosis of this DTC.
Other EVAP DTCs: P0440 – P0441 -P0443 – P0444 – P0445 – P0446 – P0447 – P0448 – P0449 – P0452 – P0453 – P0455 – P0456
Need help?
Let us fix your problem. You are most welcome our diagnosis experts have in most cases the knowledge and skills to find the cause of the error code p0442 and to solve the problems.
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"Delete Error Code Permanently, Disable DTC Error Code Function for p0442 in the ECU"
In extreme cases, we even have the option to permanently remove the specific DTC p0442 and disable the function of the specific error code in the ECU. All other fault code functions will then continue to work to protect the engine. This is different from clearing an error code with a diagnostic device. We have the option to permanently remove the function of the specific error code, so that it never comes back. Also emergency running that occurs on the specific error code can be solved in most cases.
Of course we prefer to first try to solve the cause of the error code, but sometimes the only solution is to permanently disable the DTC function of p0442.
