Oldsmobile 10456019 Knock, Sensor O/L

Fluctuations in octane ratings in today's gasoline can ignite in the inside of an engine to cause detonation which is fondly referred to as "spark knock." The ESC (Electronic Spark Control) system is to use to retard spark by as much as 20 degrees to beat this spark knock, thus giving maximum spark advance for better dynamic response and fuel economy. The ESC knock sensor mounted on the engine block generates a voltage value of between 8 and 10 volts to the ECM when spark knock is not present to allow a normal advance. If the knock sensor ever records vibrations that are beyond the normal range of tolerance, the ESC module cuts the circuit to the ECM so that the voltage produced drops to zero volts and this signals the ECM to delay the timing until the problem causing spark knock is corrected. In the case where there is a failure either at the knock sensor signal or where there is no ground at the ESC module, the signal that reaches the ECM is always high, and that makes the ECM operate on the assumption that there is no spark knock present thus lead to severe spark knock while the engine is heavily loaded, often causing a Code 43. Further, if the ESC signal to the ECM is lost there will be a continual retardation of the EST, which will slow a car's performance as well as trigger a Code 43. To remove the ESC sensor, first disconnect the cable from the negative terminal of the block of battery, then disconnect the wiring harness from the sensor, and put out the screw on the block for the removal of the sensor, lastly, to fix the new sensor on the block of a battery the process will be reversed.

When replacing the CKP sensor, a Crankshaft Position Sensor Variation Learning Procedure should be performed to avoid false diagnostic trouble codes. This involves disconnecting the battery cable, raising and securing the vehicle, removing the skid plate if necessary, disconnecting the electrical connector, removing the mounting bolt, and then installing the new sensor.

When replacing the knock sensor, disconnect the negative battery terminal and remove the distributor or oil pressure sending unit if necessary. Disconnect the electrical connector and remove the knock sensor from the engine block. Installation is the reverse of removal.

The knock sensor is responsible for detecting abnormal engine vibrations and reducing spark knock. It produces an AC output voltage that increases with the severity of the knock, which is then fed into the ECM/PCM to retard the timing.

When the notches pass the sensor, the magnetic field is altered, producing a pulsating voltage.

Release the locking tab, unplug the electrical connector, and carefully unscrew it, taking care not to damage it.

The ESC knock sensor, located on the engine block, generates and sends an alternating current voltage signal to the PCM, which then retards the timing until spark knock is eliminated.