S10/T10 Blazer 4WD V6-173 28L Ignition & Distributor Specs
Distributor: 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.
