The analog Manifold Absolute Pressure (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 intake manifold pressure. The sensor voltage increases as pressure increases. The MAP sensor allows the PCM to determine engine load 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.
Removal & Installation
- Move the ignition switch to the OFF position.
- Disconnect the pressure hose.
- Disconnect the Manifold Absolute Pressure (MAP) sensor electrical connector.
Remove the mounting screws and remove the MAP sensor.
- Installation is the reverse order of removal.
Inspect the air cleaner and inlet duct. Check all engine vacuum hoses for damage, leaks, cracks, kinks and proper routing. Check Electronic Control (EC) system wiring harness for proper connections, bent or broken pins, corrosion, loose wires and proper routing. Check the powertrain control module (PCM), sensors, and actuators for physical damage.
Basic circuit checks help to minimize pinpoint test steps by providing a procedure to diagnose harness faults associated with the Electronic Engine Control (EC) System: