98JGC - Intermittent / No Heat! It's -30 here as well!

[TorontoAnt]

I have a 98 JGC Limited 4.0L V6.

The problem is I've not been having heat blown through the Jeep. The coolant temp gauge has been showing around 40 instead of 90-100 (when the engine has been running for a long time!) and so lukewarm is being blown through. The fan works fine, as do all the settings except temperature! Ive read through some threads and the best ive done was 2 days ago wiggled all the wires and connections under the dashboard on the passenger side, hey presto! The temp gauge went up to the norm and i was getting whatever temp i wanted. Last night going home, i had to wiggle all the wires (I have no idea which one does what) and hey presto, the gauge read the actual temperature of the coolant and i got hot air! This morning it was -30, and the wire wiggling didnt work.

I havent had a coolant flush for a long time, however i cant see how this would affect gauge and only work when i wiggled the wires!

PLEASE HELP!!!!!!

[TorontoAnt]

I have been told its possibly the thermostat, could this be or is this correct?


If so i've heard they are fairly cheap to buy and replace, can i do this myself?

Thanks!

[dksob81]

Well they are cheap and easy to replace, but I don't think thats your problem seeing that when wiggle the wires your heat start working. I would look under the dash for a loose connection, I know, theres alot of wires under there and alot of searching to be done, maybe someone else will have a better answer.

but I don't think the thermostat is gonna do anything. if the T-Stat was stuck CLOSED then your Jeep would overheat, if it was stuck OPEN then the Jeep would take forever to heat up and would continue to heat up and eventually overheat.

[TorontoAnt]

Thanks for the reply, is it possible that T-stat could be stuck open, but when im banging around (not only wiggling wires) i could dislodge it, only for it to be stuck open again?

I drive 95km to work, and the coolant gauge didnt register more than 40-50 this morning :-(

[dksob81]

No, the thermostat is located on the engine. it is controlled buy the tempature of the coolant (not electrical) I think you may have a loose connection to the heater core or ac/heater control unit.