I recently installed a new air charge temp sensor on my G2 Dakota (2002 SXT 3.9). The problem is that I either had a defective replacement or I torqued it down too hard. It snapped. So I had to go down and replace the part, retracted the broken part from the head, and installed the new, new part. Question - Are there torque specs for these sensors or is it one of those "good and snug" deals? Main issue has been that I had a leaky radiator (replaced), then had a stuck open T-stat (replaced with a 195), then replaced engine coolant temp sensor, then the air charge temp sensor.... all because it won't reach temp. As of this morning, the temp was running only as high as 190, but wouldn't go any higher, per my obd2 tester. Plenty of coolant in it, no leaks, and a new water pump... So - what are the torque specs, if any for that air charge temp sensor when reinstalling, and what could the deal be with the coolant temperature not reaching 195? What is normal running temp for the 3.9? 195-220? Before I put the 195 stat in it, I put a 180 in it, and the temp would only get to about 177. now with the 195 in it, I get to around 190. Any words of wisdom???

 

That sensor just needs to be tight enough to seal, and that's it.

What brand ECT sensor did you install? It may just be inaccurate.

 

Duralast Air Charge Temperature Sensor SU3036 at Auto Zone.

 

Yeah, I really don't like Duralast anything electrical. Their quality control sucks.

I was more concerned about the coolant temp sensor. You WANT that one to be accurate.

 

In Tennesee Spring/Summer, your truck should be running 10 degrees above thermostat with ease. Sounds to me like coolant temp sensor has an offset. Agree with HeyYou, box store sensors aren't awesome. Stick to Napa Echelon or Dorman if you must.

190* as it is now should easily clean the minimum temperature code and be perfectly fine, even with the non-functional sensor. The threshold for "too cold too long" is around 175. My worry would be that the sensor won't react properly in an overheat situation.