Oldsmobile 10456287 Sensor,Knock

The magnetic pick-up assembly, on the inside of the distributor, has a permanent magnet, the pole piece having internal teeth and the pick-up coil. This is a small component in the form of a cylindrical drum having radial teeth on its outer shell which engages a toothed wheel on the distributor main shaft within the pole piece. Whenever the teeth of the timer core comes into mesh with those on the pole piece, a varying current is generated from the pick-up coil and by the help of the HEI module is converted into a distributor reference pulse.

For procedures on the position sensors, the 2 crankshaft sensors are located on the front of the engine block, between cylinder Numbers 4 and 6. Crankshaft position A sensor is situated on the upper crankcase, while crankshaft position B sensor is found in the lower crankcase. Both sensors extend into the crankcase and are sealed into the engine block with 0-rings, and they are not adjustable. The magnetic crankshaft position sensors operate similarly to the pick-up coil in a distributor; when a piece of steel, known as the reluctor, moves repeatedly over the sensor, a voltage is generated that appears as an ON-OFF signal, akin to the signal produced by breaker points in a distributor as they open and close. The reluctor ring is cast onto the crankshaft between the No. 3 and No. 4 main bearing journals, featuring 24 evenly spaced notches and an additional 8 unevenly spaced notches, totaling 32 notches. As the crankshaft completes one revolution, both A and B sensors produce 32 ON-OFF pulses per revolution, with the "A" sensor positioned 27 degrees of crankshaft revolution before the B sensor, creating a unique pattern of ON-OFF pulses for the ignition control module to recognize crankshaft position.

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.

The CKP sensor works with a reluctor wheel on the crankshaft to determine the crankshaft position.

The CKP sensor is triggered by slots on the crankshaft reluctor ring.

For models from 1988 to 1995, the ESC module is located near the throttle body. To replace it, disconnect the negative battery terminal and detach the electrical connector from the module. Remove the mounting screws and detach the module. Installation is the reverse of removal.

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.

No, thread sealant or thread locking compound should not be used on the threads of the knock sensor or the knock sensor mounting bolt.

To disconnect the CKP sensor on these engines, remove the starter motor and disconnect the CKP sensor electrical connector from the main engine harness. Remove the sensor mounting bolt and the sensor itself. Installation is the reverse of removal, ensuring that the CMP sensor mounting bolt is tightened securely.

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.