coolant temperature sensor oddity

[EUREKA]

The coolant temp sensor in my 1988 MJ 4.0 seems to be different that what is indicated by every source of information I have found.

Here is a pic of the one from my truck vs what parts stores suggest,

 

The weird thing is that the connector on my harness appears to be stock, based on the age, color and type of wire. I opened the harness quite far and there is no sign of a splice. Maybe someone replaced only the connector on the harness side? Whats going on here?

 

 

[EUREKA]

Well these connectors are the brand of auto connector I have on hand in my garage, so I may have been the jackass who did this.

[Eagle_SX4]

The sensor you pulled out is not one of the coolant sensors it is the intake air temp sensor.

 

There are 2 different coolant sensors. One for the computer and one for the gauge. The one you got goes under the manifolds straight into the engine block.

 

 

[EUREKA]

Yeah, kinda wouldn't make sense for their to be coolant in the intake. Thanks

[EUREKA]

And now I see why I had soldered the sensor lead. The sensor is discontinued.

[87MJTIM]

A Renix has three coolant sensors.

1. Temp Gauge on dash - back of the head, close to the fire wall.

2. ECM - screws in to block below manifolds

3. E-fan switch - screws in to left side of radiator to control e-fan.