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Dan, Technician
Category: Car
Satisfied Customers: 23473
Experience:  Independent Shop Experience, 2 Year Automotive Diploma, & Access to Information Database
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EVAP..malfunction..My check engine light came on

Resolved Question:

What does P0440 EVAP emission control system malfunction mean. My check engine light came on.
Submitted: 6 years ago.
Category: Car
Expert:  Dan replied 6 years ago.
This problem could consist of many things and is often hard to diagnose without a scantool to command the solenoids/valve on/off, a handheld vaccum pump to see if they and the lines hole vaccum pressure, and often a smoke machine test to check for system leaks. Possible caues could be a loose or damaged gas cap, evap canister vent valve, fuel tank pressure sensor, fuel filler pipe or hose, evap vapor lines, purge lines, evap canister, or evap purge valve. You can make sure the gascap is tight and the seal on it is good if so the next step would be to get a handheld vaccum pump and make sure all of the lines hold vaccum. Let me know if you have questions, thanks.
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