. How can i tell which one without replacing both?
What is your question?
The code on my car says 440. But its showing both EVAP Canister Purge Valve or the evaporative control Valve. How can I tell which one with out replacing both? My check engine light just came on. The problem has been going on for a couple of weeks. Didn't notice the problem until the engine cut off when u pump gas and then have problems starting it. Or when u unscrew the cap it cut off n have problems starting.
What makes this problem better or worse?
When I'm gasing up.
How long has your 2014 Chevrolet Impala had this problem?
RepairPal Certified shops can diagnose and repair your 2014 Chevrolet Impala. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.
Typically a failed VENT VALVE SOLENOID will result in difficulty refueling.
A failed PURGE VALVE will result in temporarily flooded engine which results in difficulties starting engine after refueling..
Holding accelerator pedal to floor will help clear flood engine and aid with starting after refueling UNTIL repairs can be completed.
All that said - a professional scan tool can perform functional test of the EVAP components to check for proper operations - when used by knowledgeable personnel.
As a side note - habitually topping off fuel tank when refueling will dramatically increase the possibility of failed EVAP components!!
Good luck!
