Vapor Pressure Sensor: Inspection

2004 Toyota Matrix XR, FWD, StandardSECTION Inspection
WARNING: This page is about a different car, the 2004 Toyota RAV4. However, it is still accessible from the selected car via links, so may be relevant.
  1. REMOVE LUGGAGE COMPARTMENT BOX 
  2. REMOVE FLOOR SERVICE HOLE COVER 
  3. REMOVE VAPOR PRESSURE SENSOR 
    1. Remove the 2 bolts and No. 3 fuel tank protector.
    2. Disconnect the vapor pressure sensor connector.
    3. Remove the clip and vapor pressure sensor.
  4. INSPECT VAPOR PRESSURE SENSOR 
    1. Turn the ignition switch ON.
    2. Using a voltmeter, measure the voltage between terminals VC and E2 of the wiring harness side connector.

      Voltage: 4.5 to 5.5 V 

    3. Fig 1: Measuring Voltage Between Terminals VC And E2 Of Wiring Harness Side Connector Using Voltmeter
      G02639482Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Turn the ignition switch OFF.
  5. INSPECT POWER OUTPUT OF VAPOR PRESSURE SENSOR 
    1. Connect the vapor pressure sensor connector.
    2. Turn the ignition switch ON.
    3. Connect a voltmeter to terminals PTNK and E2 of the ECM, and measure the output voltage under the following conditions:
      1. Apply vacuum (2.0 kPa (15 mmHg, 0.59 in.Hg)) to the vapor pressure sensor.

        Voltage: 1.3 to 2.1 V 

      2. Release the vacuum from the vapor pressure sensor.

        Voltage: 3.0 to 3.6 V 

      3. Apply pressure (1.5 kPa (15 gf/cm2 , 0.22 psi)) to the vapor pressure sensor.

        Voltage: 4.2 to 4.8 V 

    4. Turn the ignition switch OFF.
    5. Fig 2: Inspecting Power Output Of Vapor Pressure Sensor
      G02639483Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  6. REINSTALL VAPOR PRESSURE SENSOR 
    1. Reinstall the vapor pressure sensor and clip.
    2. Reconnect the vapor pressure sensor connector.
    3. Reinstall the 2 bolts and No. 3 fuel tank protector.
  7. REINSTALL FLOOR SERVICE HOLE COVER 
  8. REINSTALL LUGGAGE COMPARTMENT BOX 
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.