Dakota 2WD V6-239 3.9L (1987)
Coolant Temperature Sensor/Switch (For Computer): Description and Operation
Coolant Temperature Switch
On V6-238 engines, the coolant switch is located on front left side of intake manifold. It operates by supplying a signal to the computer when the
engine coolant temperature is below 150~ F. This information is required to prevent a change in air fuel ratio until engine operation temperature is
reached. In addition, when the engine temperature reaches 150° F., the computer will switch the air pump injection from upstream to downstream into the
exhaust system and will allow the charcoal canister to purge.
