The MAP sensor is a variable capacitor sensor that is supplied a 5-volt reference signal by the PCM and returns a voltage signal to the PCM relative to the intake manifold pressure. The sensor voltage increases as the pressure increases. The MAP sensor allows the PCM to determine the engine boost to calculate fuel quantity. In addition, the MAP signal is used to control smoke by limiting fuel quantity during acceleration until a specified boost pressure is obtained, and is used by the PCM for EGR system calculations and control.
A MAP signal concern detected by the PCM causes the PCM to calculate an estimated manifold pressure based on known engine conditions.
Removal & Installation
6.0L Diesel Engine
- Before servicing the vehicle, refer to the Precautions section.
- Turn the ignition switch to the OFF position.
- Disconnect the manifold absolute pressure (MAP) sensor.
- Disconnect the pressure hose.
- Disconnect the electrical connector.
- Remove the mounting screws and the MAP sensor.
- To install, reverse the removal procedure.
Before servicing the vehicle, refer to the Precautions section.
WARNINGUse only a high-impedance multimeter, otherwise damage to the PCM and/or sensors can result.
- Disconnect the pressure hose from the MAP sensor.
- With the key ON, engine OFF, connect the Pressure Adapter Kit 014-00761, or equivalent (gauge bar), and apply pressure to the MAP sensor.
- Backprobe MAP sensor connector pin 2 and measure the voltage between pin 2 and ground.
Compare the values with the pressure/voltage table.