LEMON Manuals: Even more car manuals for everyone
Home >> Chevrolet >> 2017 >> Malibu LS >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 29 (Engine Controls And Fuel - 1.8L (LKN) - DTC P0446 To DTC P2635 And Diagnostic Information And Procedures) >> Diagnostic Information and Procedures >> DTC P0451-P0454 or P1464: Fuel Tank Pressure Sensor >> Circuit/System Verification

Circuit/System Verification

WARNING: This page is about a different variant/trim than selected.
NOTE:
  • The order of these steps is important. If not followed properly you will be bleeding off any pressure or vacuum in the system and not see any change in the EVAP leak detection pump sensor.
  • Read the instructions for P0451 in their entirety before proceeding to understand what is being required.
  • Ambient and vehicle component temperature must be above 0°C (32°F) to command the switching valve or vacuum pump. This prevents erroneous results and damage to the EVAP leak detection pump assembly.

P0451

  1. Verify DTC P0452 or P0453 is not set
    • If the DTC sets 

      Refer to Circuit/System Testing

    • If the DTC does not set 
  2. Vehicle in Service Mode.
  3. Record the scan tool Fuel Tank Pressure Sensor parameter, pressure or vacuum.
  4. The Fuel Tank Pressure Sensor parameter should be 0.07 in H2O, 0.01 kPa (0.00 PSI) after 5 s.
    • If not within the specified range 

      Verify the following conditions do not exist:

    • A restriction in the EVAP canister or vent lines
    • The reference port on the fuel tank pressure sensor is obstructed

      Repair or replace as necessary

    • If within specified range 
  5. Command the EVAP leak detection pump ON using the scan tool EVAP Test. Get the fuel tank pressure sensor parameter to -11.56 in H2O, -2.88 kPa (-0.42 PSI) or greater. This may take several seconds.
    NOTE: Use of any control function other than EVAP Test will not create a vacuum in the system.
    NOTE: Vacuum will decay exiting the EVAP Test and going to step 8. This is normal. There should be sufficient vacuum left to perform steps 8 and 9.
  6. Record the scan tool EVAP Leak Detection Pump and Fuel Tank Pressure Sensor parameters, reading one.
  7. Perform each step listed below in order:
    1. Select scan tool Fuel Tank Pressure Sensor Test.
    2. Command the EVAP Leak Detection Pump Switching Valve Command to Not Venting.
    3. Wait for 3 s.
  8. Record the scan tool EVAP Leak Detection Pump and Fuel Tank Pressure Sensor parameters, reading two.
    NOTE: Wait for 15 s while observing the parameters then click the pause button on the scan tool to retain the parameters.
  9. Press the scan tool Release Control button after recording the parameters.
  10. Subtract the EVAP leak detection pump reading 2 from EVAP leak detection pump reading 1. This value equals what the fuel tank pressure sensor, reading two, should be (EVAP leak detection pump reading 2 - EVAP leak detection pump reading 1 = fuel tank pressure reading 2). The fuel tank pressure sensor should be within 3 in H2O, 0.749 kPa (0.11 PSI) of the subtraction just performed.
    NOTE: The subtraction results and Fuel Tank Pressure parameter should be negative since a vacuum was pulled on the system.
    • If not within the specified range 

      Verify the following conditions do not exist:

    • A restriction in the EVAP canister or vent lines
    • The reference port on the fuel tank pressure sensor is obstructed

      Repair or replace as necessary

    • If within the specified range 
  11. All OK.

P0452 and P0453

  1. Check for DTC P0641, P0651, P0697, P06A3 or P06D2 is not set.
    • If none of the DTCs are set 
  2. Open the capless fuel fill flapper doors with CH-44284-2  .
  3. Vehicle in Service Mode.
  4. Verify the scan tool Fuel Tank Pressure Sensor parameter. It should be 2.67 V at 0 kPa (0 PSI).
    • If not within the specified range 

      Refer to circuit/system testing.

    • If within the specified range 
  5. All OK.
scientia non olet · About LEMON Manuals