I was looking under the hood of my 87 XJ and noticed that there is a plug that isnt screwed in and that the one that used to be in its spot needs to be tapped out. Anyways, I have included a picture and would like to know if anyone knows what this is off the top of their head and if it needs to be hooked up.

Thank you in advance


Here is link to pic

 

That would be your MAT sensor, and yes, it should be plugged in. Not having it plugged in should be hurting your gas mileage. I don't know what's in the hole for the MAT sensor, but the thing hanging right behind the throttle linkage is what should be in that hole and plugged in.



^^MAT sensor^^

 

Hmm..
Looks like someone plugged the hole for the MAT sensor and just left it there.
It looks like you need a new one too, theyre like 20 bucks. Buy a new one and put it in that hole...

 

Thanks guys. You are all a huge help. I really appreciate it a lot. I will have to find someone to tap out that hole now...