DURA-Spark II With Universal Ignition Module (UIM)

Some models have a special electronic control module (UIM) with a third connector and 3 wires. The UIM can be identified by Yellow wire grommet on module and third wire connector. See Fig 1. This connector attaches to a special switch which is either a distributor vacuum modulator valve, or an ignition barometric pressure switch.

Fig 1: Dura-Spark II System w/ Universal Ignition Module (UIM)

Fig 2: Dura-Spark II Ignition System Wiring Diagram

This switch allows base engine timing to be modified to suit altitude, or engine load conditions. All other operating characteristics of the module are the same as for Dura-Spark II systems without special switch.