Quote:
Originally Posted by Tripod
By the way, I have no idea how this was temperature related unless expansion by heat may have adversely affected the 'failing' reference sensor. The unusual aspect of this part failure was that the car started cold normally and ran normally under all conditions and temperatures. To me this implies that the reference sensor is only used by the ECU during start-up. Only conjecture by me at this time.
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There is a pin pressed into the flywheel at 62 degree before TDC. As the pin passes over the sensor it distrubs the magnet field from the sensor. The ECU will see this signal and use this signal along with the cam and speed sensor and send a trigger signal to the coil to cause a spark.
The CKP or timing reference sensor is a magnetic sensor and as we all remember from high school physics a magnet looses it strength when heated.
The CKP is used by the ECU, but if it should fail it will default to a value at startup, the engine will remain running but will not restart until the signal is restored. On the other hand should the RPM (speed) sensor fail the engine will not start and if the engine was running it will die.
