How do you correct a p440 code - 1999 Chevrolet Monte Carlo

https://www.fixya.com/cars/t19464249-evap_vent_valve_solenoid_location

You need a Catalytic converter and possibly a Evap. cannister

Check the distributor cap for cracks.

EECS.pruge flow.

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.

the code ur are getting on your envoy is a emiision problem first you could try a new gas cap its a known problem in setting this code ...hope this helps

Answered the other similar question

under the rear of the vehicle under the trunk

thats a evap code should not turn the car off you are heaving some other issue

The P440 means that Evaporative Emission Control System.
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