SPACER-SPECIAL 1745643 - Caterpillar

Table 1
Tools Needed Quantity
1U-5470 Engine Pressure Group 1 Absolute pressure - Absolute pressure is the gauge pressure plus the local barometric pressure.Gauge pressure - Gauge pressure is the absolute pressure minus the local barometric pressure.The manifold air pressure sensor is also called the air inlet pressure sensor. The air inlet pressure sensor measures the absolute inlet manifold air pressure.To verify that the air inlet pressure sensor is accurate, use the Caterpillar Electronic Technician (ET) to read the "Inlet Manifold Air Pressure (abs)" when the engine is stopped. The correct pressure will be the ambient barometric pressure.Use the following procedure to compare the reading from the air inlet pressure sensor with a reading from the 1U-5470 Engine Pressure Group.Note: The air inlet pressure sensor may be installed at either end of the inlet manifold. The actual location depends on the configuration of the control system.
Illustration 1 g00929850
Right view at the rear of the engine
Plugs in the air inlet manifold
Remove one of the plugs from the air inlet manifold. Connect a line from the opening to a pressure gauge from the 1U-5470 Engine Pressure Group. Operate the engine under a load. Use Cat ET to read the inlet manifold air pressure. Read the pressure gauge from the 1U-5470 Engine Pressure Group and add the local barometric pressure to the reading. Compare the calculation to the reading from Cat ET.