S15/T15 4WD Jimmy L4-121 2.0L VIN Y 2-bbl (1983)
Crankshaft Position Sensor: Description and Operation
On all models with full function systems except V6-229 (1983 - 84 VIN code 9) engines, the ``R'' terminal on the 7 terminal ignition module provides
reference pulses to the ECM indicating engine RPM and crankshaft position.