Temp gauge issue

[sgtmac]

So I purchased a 2 door 98 XJ, 4.0 w/ 2wd-4wd conversion. This thing has been bubbed to death and as I have been messing with it, have come to realize it is going to be more of a project than I want to deal with at the moment.

Why people fix/replace/upgrade stuff all half-ass'd is beyond me on me, idiots! But I digress.

Recently my temp gauge is all over the place, stuck at 100, moving up and down just kinda randomly, never seen this before. Has coolant in the Rad, overflow etc. Could it be the switch, gauge etc? I am trying to fix on the cheap so keep that in mind.


Thanks
Rich

[Brasscatz]

It's most likely the coolant temp sensor that screws into your thermostat housing. You can get them for pretty cheap on RockAuto.com.

Another question... is your check engine light on? Whether it is or not, check the codes and see if there's one stored. Mine was doing the same thing and it was throwing a code. Here's how to check without having to hook up a scanner: http://www.xjtalk.com/showthread.php?t=11574

[sgtmac]

That was what I was hoping for. For some reason that code trick does not work w/ my XJ. I have no CEL at the moment, but will check for stored codes.

Thanks for the response.

[XJ Wheeler]

Make sure of its tightness first hand as well.

:nothingtoadd::D

[bigjim350]

Good information but i must correct you.

It is the sending unit on the rear left side of the head that controls the gauge. If you do need a replacement be sure to get one specifically for the gauge, not the one for the idiot light.

Make sure of its tightness first hand as well.

Good info but I must correct YOU :p
On 97+ xj's there is only 1 sensor and its in the t-stat housing.

[XJ Wheeler]

Good info but I must correct YOU :p
On 97+ xj's there is only 1 sensor and its in the t-stat housing.

:bang: Sorry, Brasscatz. Don't have much experience in '97+, just assumed they hadn't changed it. Thanks bigjim for the correction, i'll edit mine so i don't lead anyone off course.

[Brasscatz]

No worries at all, Jake. :) you know more than I do about these jeeps for sure. I only recently learned about the coolant temp sensor when I had to replace mine

[GAPANDA]

Sounds like an issue mine had. Discovered that it did NOT HAVE a thermostat!
Bought a new one at the local dealer after reading several posts of failed aftermarket units. Be prepared if you do this as well. My price was $25 before some negotiations. Got them down to $19 by threatening to go elsewhere.
After this along with a quick flush of the heater core and new upper radiator hose runs straight up 210 degree solidly.

Good Luck.