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Home >> Chevrolet >> 2003 >> Impala LS >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System Self-Diagnostics - 3.8L >> Diagnostic Tests >> DTC P0440: EVAP System >> Test Description
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Test Description

The numbers below refer to the step numbers in the diagnostic procedures.

  1. 2

    This step verifies that a failure condition is active.
  2. 4

    Introducing smoke in 15 second intervals may allow smaller leak areas to be more noticeable. When the system is less pressurized, the smoke will sometimes escape in a more condensed manner.
  3. 6

    This step verifies proper operation of the FTP sensor.
  4. 7

    A normal operating FTP sensor should increase above 5 in. H2O and stop between 6-7 in. H2O.
  5. 9

    This step tests the EVAP purge solenoid vacuum source between the EVAP purge solenoid and the intake manifold for restrictions or blockages.