QuestionWe're original owners; over 102,000 miles
The malfunction light came on after going over a bump. the diagnostic code at Autozone was 0441. i took it to a mechanic who couldn't find a problem. he cleared the light. After a few days, the light came back on. The gas cap is tight... any ideas?
AnswerJoan, great milage on an excellent choice for a vehicle.
Evaporative Emission Control System Incorrect Purge Flow - Code P0441 -
This indicates that a part of the EVAP control system is no longer fuctioning correctly. The EVAP system consists of many parts, including (but not limited to) the gas cap, fuel lines, carbon canister, purge valve, and other hoses. 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.
EVAP emission canister purge is contolled by a valve which allows engine vacuum to pull stored fuel vapors from fuel tank into the engine to be burned, rather than be vented to atmosphere. A vacuum switch is used to detect when flow exists. If the PCM commands purge and sees that the switch is closed (indicating no detected purge flow) P0441 is set.
Okay in english? Likely, no symptoms will be discernible to the driver, other than the illuminated Check Engine Light. When this activates just take it too AutoZone or another autoparts shop that can read and clear the codes for you. For free.
Causes - Bad vacuum switch, broken or damaged EVAP line or canister, open in PCM purge command circuit, open or short in Voltage feed circuit to Purge Solenoid, faulty purge solenoid, restriction in EVAP solenoid, line or canister; corrosion or resistance in purge connector, bad PCM.
