Scoupe L4-1468cc 1.5L SOHC (8 VALVE) (1991)
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Crankshaft Position Sensor: Description and Operation
Distributor (Crank Angle and #1 TDC Sensors)
Crank Angle And #1 TDC Sensor Location
The Distributor consists of a housing, shaft, drive gear, distributor cap and rotor, and houses the crankshaft angle and the No.1 cylinder TDC sensors.
The drive gear (mounted on the end of the distributor shaft) drives the shaft at cam shaft speed. On the other end of the shaft the rotor is mounted. When
properly timed the rotor carries current from the coil tower in the distributor cap to the correct spark plug electrode for the designated firing order.
Crank Angle And #1 TDC Sensor
The crankshaft angle sensor and the No.1 cylinder TDC sensor are composed of a disc and unit assembly. The disc is a metal disc which has four
light-transmission slits located 90° apart around its circumference. There is also one additional slit located inward from these four. The inner slit is for
the No.1 cylinder TDC sensor, and the outer slits are for the crankshaft angle sensor.
The disc is affixed to the distributor shaft. When the shaft rotates, the slits in the disc are optically read by the unit assembly. The unit assembly, in order
to be able to detect the two types of slits, incorporates two luminous diodes and two photo diodes. There is a very slight clearance between the luminous
diodes and the photo diodes, and the disc rotates within this space.
Crank Angle And #1 TDC Sensor System
The light emitted from the luminous diodes reaches the photo diodes each time the disc turns. When the photo diodes receive the light transmitted, they
