I have a P0440 code.Evap System no flow during purge.
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2001 Chevrolet Blazer Question: EVAP system
Answer #1DaveJHM June 19, 2011, 23:02Master
Basically, this code indicates a large leak or large restriction that is preventing the EVAP system from developing / holding vacuum.
Test to ensure your gas cap is secure. Other than that, a further diagnostic test must be performed using proper test equipment, including a smoke vapor machine. Anything other than that will be guess work.
Replysimeonteague, March 04, 2012, 14:51Rookie
Thanks, just guessing how much would that cost