Engine code 0456 ( evaportive emission control system leak detected, very small leak ) installed a new OEM gas cap and reset the computer. Worked fine for 1 1/2 week and check engine code came back? Cleand filler tube, reinstalled gas cap reset computer.

p0442 means Evaporative Emission Control System Leak Detected (small leak)

What does that mean?
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.
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: A loose or improperly affixed gas cap A non-conforming gas cap (i.e. not factory/original brand) A small leak/hole in a fuel vapor hose/tube Other small leak in EVAP system Faulty vent o-ring seal Defective vent valve Defective purge valve Defective leak detection pump
Possible Solutions
With a P0442, the most common repair is to: Remove and reinstall the gas cap, clear the codes, and drive for a day and see if the codes come back. Otherwise, replace the gas cap (we recommend an OEM not aftermarket part), or Inspect the EVAP system for cuts/holes in tubes/hoses More advanced troubleshooting steps include: Using an advanced scan tool, perform an EVAP leak test Verify operation of the EVAP purge solenoid / valve Perform a smoke test to see where the leak is

DTC P0442 - Evaporative Emission Control System Leak Detected (small leak)
This 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. You likely won't notice any drivability problems.

A code P0442 most likely means one or more of the following has happened:
- A loose or improperly affixed gas cap
- A non-conforming gas cap (i.e. not factory/original brand)
- A small leak/hole in a fuel vapor hose/tube
- Other small leak in EVAP system
- Faulty vent o-ring seal


With a P0442, the most common repair is to:
- Remove and reinstall the gas cap, clear the codes, and drive for a day and see if the codes come back.
- Otherwise, replace the gas cap, or
- Inspect the EVAP system for cuts/holes in tubes/hoses

Hope this helps; remember to rating this answer and leave a testimonial comment. Thabk you for using Fixya.

P0442 - Evaporative Emission Control System Leak Detected (small leak)

This 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.

Symptoms: You likely won't notice any drivability problems.

Causes: A code P0442 most likely means one or more of the following has happened:
A loose or improperly affixed gas cap
A non-conforming gas cap (i.e. not factory/original brand)
A small leak/hole in a fuel vapor hose/tube
Other small leak in EVAP system
Faulty vent o-ring seal

Possible Solutions: with a P0442, the most common repair is to:
Remove and reinstall the gas cap, clear the codes, and drive for a day and see if the codes come back.
Otherwise, replace the gas cap, or
Inspect the EVAP system for cuts/holes in tubes/hoses


Check it, test it and send us news.

P0442 - Evaporative Emission Control System Leak Detected (small leak)

This 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.

Symptoms: You likely won't notice any drivability problems.

Causes: A code P0442 most likely means one or more of the following has happened:
* A loose or improperly affixed gas cap
* A non-conforming gas cap (i.e. not factory/original brand)
* A small leak/hole in a fuel vapor hose/tube
* Other small leak in EVAP system
* Faulty vent o-ring seal

Possible Solutions: With a P0442, the most common repair is to:
* Remove and reinstall the gas cap, clear the codes, and drive for a day and see if the codes come back.
* Otherwise, replace the gas cap, or
* Inspect the EVAP system for cuts/holes in tubes/hoses

Hope helps.

Evaporative Emission Control System Leak Detected (small leak)
This 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.

Causes: A code P0442 most likely means one or more of the following has happened:
* A loose or improperly affixed gas cap
* A non-conforming gas cap (i.e. not factory/original brand)
* A small leak/hole in a fuel vapor hose/tube
* Other small leak in EVAP system
* Faulty vent o-ring seal

Possible Solutions: With a P0442, the most common repair is to:
* Remove and reinstall the gas cap, clear the codes, and drive for a day and see if the codes come back.
* Otherwise, replace the gas cap, or
* Inspect the EVAP system for cuts/holes in tubes/hoses


Keep us updated.

P0442 - Evaporative Emission Control System Leak Detected (small leak)

This 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.

Symptoms: You likely won't notice any drivability problems.

Causes: A code P0442 most likely means one or more of the following has happened:
* A loose or improperly affixed gas cap
* A non-conforming gas cap (i.e. not factory/original brand)
* A small leak/hole in a fuel vapor hose/tube
* Other small leak in EVAP system
* Faulty vent o-ring seal

Possible Solutions: with a P0442, the most common repair is to:
* Remove and reinstall the gas cap, clear the codes, and drive for a day and see if the codes come back.
* Otherwise, replace the gas cap, or
* Inspect the EVAP system for cuts/holes in tubes/hoses



P0445 - Evaporative Emission Control System Purge Control Valve Circuit Shorted.
Possible Solutions: with a P0445, the most common repair is to:
* Bad or loss contact wires
* Check harnesses, replace it


Hope helps (remember to rate this).

P0442 OBD-II Trouble Code - Evaporative Emission Control System Leak Detected (small leak)

What does that mean?
This 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.


Symptoms
You likely won't notice any drivability problems.


Causes
A code P0442 most likely means one or more of the following has happened:
* A loose or improperly affixed gas cap
* A non-conforming gas cap (i.e. not factory/original brand)
* A small leak/hole in a fuel vapor hose/tube
* Other small leak in EVAP system
* Faulty vent o-ring seal


Possible Solutions
With a P0442, the most common repair is to:
* Remove and reinstall the gas cap, clear the codes, and drive for a day and see if the codes come back.
* Otherwise, replace the gas cap, or
* Inspect the EVAP system for cuts/holes in tubes/hoses




Fig. EVAP vent solenoid (2) on 3.1L, 3.4L, 3.5L & 3.8L, showing the connector (1) and vapor line (2)




Fig. EVAP canister purge solenoid location on 3.1L & 3.4L




Fig. EVAP purge solenoid valve (3) location on 3.5L




Hope this help, good luck.

Check all of your EVAP lines and the charcoal canister. Also check the lines and overflow line from the gas cap to the gas tank.

This could be a # of problems but try these: Remove gas cap and carefully inspect it and the fuel filler neck for small cracks and/or distortion/dirt. Under the hood there is a small green cap which is the test port for the evap system, remove it and check the schrader valve to be sure its tight ( left hand threads!!!). Check all hoses attached to this for cracks/breaks.Other than this a diagnostic will have to be ran with a smoke machine to pin point leaks or valve/switch/solenoid/canister failure.

You have a vaccum leak somewhere, try the map sensor vaccum or the EGR Control valve vaccum