Dakota 2WD V6-239 3.9L (1987)
Vacuum Switch: Description and Operation
Fig. 6 Spark control computer & vacuum transducer location. 1987 Dakota w/4-135 & V6-238 engines
The vacuum transducer is located on the computer and it provides the computer with information on engine vacuum, Fig. 6. It is used to control spark
advance and air fuel ratios. And indicates engine load.