The Knock Sensor is mounted in the cylinder head or in the left side of the cylinder block. See Figure 40524 . The sensor works in conjunction with a Signal to Noise Enhancement Filter (S.N.E.F.) module which is mounted to a bracket located on the left side of the cylinder block.
1. S.N.E.F. Module
7. Regulator Gas Inlet Tee
2. Air Compressor
8. Manifold Pressure "Boost" Sensor
9. Barometric Pressure Sensor
4. Fuel Mixer
10. Oxygen Sensor Interface Module
11. DDEC ECM
6. Low Pressure Regulator
12. Knock Sensor
Knock Sensor and Signal to Noise Enhancement Filter (S.N.E.F.) Module for Series 50G Automotive
The Knock Sensor and S.N.E.F. module provide a signal to DDEC which is proportional to the knock level. DDEC uses the data in engine protection logic. The knock sensor is electrically connected to the S.N.E.F. module through the sensor wiring harness. The S.N.E.F. module is electrically connected to the ECM and to battery power through the engine sensor harness. The output from the S.N.E.F. module can be monitored using the Diagnostic Data Reader (DDR). The output is displayed as knock level.
The knock sensor and S.N.E.F. module are not serviceable and must be replaced as an assembly. No adjustments are required.
Remove the knock sensor as follows:
Remove the S.N.E.F. module as follows:
Install the knock sensor as follows:
Install the S.N.E.F. module as follows: