BLOCK GP-BOOM SHEAVE 3001624 - Caterpillar

Manifold Air Pressure Sensor
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Previous design of the manifold air pressure sensor
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New design of the manifold air pressure sensorThe EIS control module supplies approximately 13 VDC to the manifold air pressure sensor. The sensor monitors the absolute inlet manifold air pressure. The sensor sends a signal to the EIS control module. The EIS control module has an interpreter that uses the signal to calculate the engine load. If a timing map that is sensitive to load is selected, the EIS control module adjusts the ignition timing according to the calculated load.The EIS control module will generate a diagnostic code if problems with the manifold air pressure sensor electrical circuit are detected.Note: If the engine has the air/fuel ratio control, the ECM sends information from the inlet manifold pressure sensor to the EIS control module. The information is sent via the Cat Data Link. If the engine does not have the air/fuel ratio control, the inlet manifold pressure sensor sends information directly to the EIS control module.Detonation Sensors
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Previous design of the detonation sensor (1) Buffer module (2) Accelerometer
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New design of the detonation sensor (2) AccelerometerA previous detonation sensor includes buffer module (1) , accelerometer (2) , and wiring. A current detonation sensor includes an integral buffer module, accelerometer (2) and wiring. A detonation sensor is located on the upper cylinder block on each side of the engine. Each sensor monitors one bank of cylinders. The EIS control module supplies approximately 13 VDC to the sensors.The detonation sensors provide an electrical signal of the mechanical engine vibrations to the EIS control module. The accelerometers provide electrical signals to the buffer modules. The buffers provide a signal with an offset of approximately 6 VDC to a filter in the EIS control module. The signal indicates mechanical engine vibrations. The frequency of the signal corresponds to the mechanical frequency of the vibrations. The amplitude of the signal is proportional to the intensity of the vibrations.The EIS control module monitors the signals in order to determine the presence and the severity of detonation. The EIS control module retards the timing in order to limit detonation levels.The retardation of timing is the first level of protection against detonation. The EIS control module can retard timing by as few as 0.1 degrees for light detonation levels. The timing can be retarded up to 6 degrees for severe detonation.As the detonation level decreases, the EIS control module will begin to advance the timing out of the detonation retarded timing. The advance is proportional to the level of detonation. The rate is faster for lighter detonation. The fastest rate of advance is 2 degrees per minute.Engine shutdown is the second level of protection against detonation. If retardation of the timing is unsuccessful and the detonation continues at severe levels, the EIS control module will signal for an engine shutdown.Protection from detonation is enabled under the following conditions:
The inlet manifold air pressure reaches an absolute pressure of 60 kPa (241 inches of H2O).
If a diagnostic