The Manifold Absolute Pressure Sensor (MAP) is threaded into the intake manifold. See Figure 27856 . The Series 50G natural gas engines use a wide range sensor that allows pressure measurement under conditions of either manifold vacuum or boost.
1. Intake Manifold
2. Intake Manifold Inlet
6. Air Temperature Sensor
3. Intake Manifold Gasket
4. Cylinder Head
8. Manifold Absolute Pressure Sensor
Manifold Absolute Pressure Sensor Series 50G
This device is a pressure sensor that sends an electrical signal to the ECM. The ECM uses this information to compute the amount of air entering the engine. Fuel supply is regulated by the TBS information to control engine air fuel ratio. The MAP information is also used to control ignition timing.
The MAP is non-serviceable and must be replaced as an assembly. No adjustment is required.
Remove the MAP as follows:
Install the MAP as follows:
Note: The MAP is an electronic device. Use care during installation.