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Home >> GMC >> 1999 >> Forward Control 7.4 B >> Repair and Diagnosis >> External Pages >> Different car >> Section 79 (Engine Control System Self-Diagnostics - 3.4L) >> Diagnostic Tests >> DTC P0440: EVAP System >> Test Description
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Test Description

WARNING: This page is about a different car, the 2002 Pontiac Grand Am, 2002 Oldsmobile Alero, 2002 Chevrolet Monte Carlo, and 2002 Chevrolet Impala. However, it is still accessible from the selected car via links, so may be relevant.

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

  1. 4

    This step is used to verify if a leak is present.
  2. 6

    This step verifies proper operation of the FTP sensor.
  3. 9

    This step tests the EVAP canister purge valve for a restriction or blockage.