See Figure 1
The absolute pressure sensor is connected to the MAP/BARO switch solenoid valve by a hose. The sensor detects ambient barometric pressure and intake manifold pressure, and sends a voltage signal to the ECM. As pressure increases, the voltage rises. The absolute pressure sensor is not used to control the engine system. It is only used for on-board diagnosis.
See Figures 2 and 3
- Remove the absolute pressure sensor with its electrical harness connected.
- Disconnect the vacuum hose from the sensor.
- Turn the ignition switch ON .
- Backprobe the sensor connector and check output voltage, from the white wire and ground.
- The voltage should be 3.2-4.8 volts.
- Connect a hand powered vacuum pump and apply a vacuum of 7.87 in. Hg (26.7 kPa).
- Voltage should be 1.0-1.4 volts lower than the value in Step 5.
- If voltage is not within specification or does not respond as specified, check the power and ground circuits.
- If the power and ground circuits are okay, the sensor may be faulty.
REMOVAL & INSTALLATION
- Label and disconnect the electrical harness from the sensor.
- Label and disconnect the vacuum hose from the sensor.
- Remove the sensor mounting screws.
- Install the sensor and tighten the screws securely.
- Connect the vacuum hose to the sensor.
- Connect the electrical harness to the sensor.