i have a 98 dodge 1500 with the 318, i just replaced my stock themo. 195 with a 180 themo. in the process i noticed right there at the thermostat there is a little plug in wire that you can plug something into. if your looking dead over the thermostat from the front of the truck, it is just to the right of it on the drivers side. nothing is plugged into mine and im kind of concerned of what is sopose to be plugged in there or better yet...what is it? if you dont have a clue what im talking about i can get a picture of it, but it wont be easy to because of my phone lol. but any suggestions???

 

hmm, sounds like coolant sensor or sender, would be near the tstat in the intake

 

hmm sounds like the coolant temp sensor.. is the temp guage working properly?

 

yeah everything is working fine, i just replaced my 02 sensor this morning now its throwing a code now p0132 which is high voltage on the o2 sensor...does anyone know whats up with that?

 

was that the same code showing up before you replaced it? If it is have you cleared the codes yet?

 

and the only other two sensers that i know of by the t-stat is the coolant sensor and sender unplugged sender will make a rough idle

 

Oh ok nah it never came on before I put the new one on but I cleared it and it hasn't came back on.....yet lol. But the reason I replaced it in the first place was because my hissing noise and it was missing really bad at warm up but that solved my problem. You can look at my previous post's and see what my problems were....just too much to type

 

do you have a sensor with no wire plugged into it ?
or
a wire not plugged into a sensor ?

the older models had 2 temp sensors in the intake, one for the gauge and one for the pcm (or something like that). the newer models have only one sensor. 97/98 might have been a crossover year. if you've got no temp related issues and your gauge is working fine, i'd ignore it.

 

The plug on left is the sender and the right is the sensor IIRC. (thermostat remove and plug with cloth)


This second picture show the sensor plug smack dab in the middle unplug. It follows into the other wires for the injectors on passenger side valve cover. I would check to see if it is there, and that it wasn't hack off.