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
P0456 - Evaporative Emissions System - Small leak detected
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.
Potential Symptoms: 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: 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.
Test it; keep us updated and remember to rate this answer.
SOURCE: CODES,P0442,P0455,P0456,P1684
Yes, the P1684 on the Chrysler line does not indicate a fault. My sebring had codes p0442 and p0456 both indicating very small evep leaks. When I did the 3 time switch on of the ignition, the odometer readout gave me the p1684 first and then the other two. The scanner at the garage only indicated two "very small evap leaks" one for the second two codes. Clearly the first is a status indicator such as recent battery disconnect or another non problematic indicator. Wouldn't it be great if these manufacturers at least gave you the information to identify what their dummy lights are telling you so you didn't have to go on faith at the garage?
SOURCE: code P0456,P0455, &P0442
hello po442 ,po455,po456 is leak detected possible, check the gas cap , basicaly you have a leak that is larger than 0.020' and smaller than 0.040' in the gas evaporative system use your nose to find this one thanks
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