No Heat

Hey all, So been busy as hell lately, but the wifes XJ has little to no heat. I tried flushing the heater core and flow seemed good. temp gauge goes up to about 180 or so. Any suggestions?

Also forgot I did replace the T-stat also cause it was running hot over the summer. Used a 180 stock one

Always post the year/engine of your XJ as there are some significant differences along the way from 84-01.

For instance, earlier models have a heater control valve that allows hot coolant to get to the core. 84-96 have these I believe. And those are always suspect.

If you have a 4.0, the target temperature for coolant/engine is 200-210. You may want to verify your coolant temp by pointing an infrared point and shoot thermometer directly at the thermostat housing.

195 is the best stat for most applications. But your 180 stat is not the cause of little or no heat.

Also have to verify the "blend door" operation so that the hot air is being routed properly into the cab.

Sorry I forgot that Jeeps are so particular, Its a '98 with a 4.0. I did check the temp with the temp gun and its up right where the T-stat should be + or - a few degrees.

Feel both heater hoses both should be pretty close in temp. If they are you might have a blend door issue. If one is hot one is cold or only slightly warm, your core is clogged up.

97 and newer XJ'S use a vacum system to operated the blend door and mode doors. make sure there is not a broken vacum hose going to the dash. check all operations . does the system blow air where it is supposed to. if air come out of all the vents as where the controls are set then you may have a bad blend door or actuator.

oh yea the Jeeps like the 195 t stat. better heat.

Ok Thanks for the info guys that is kind of a problem that I have been thinking about. I will be sure to check the hoses when the wifey gets home. Hoping is just the actuator and not a plugged heater core.

Running the 180 degree thermostat won't change the final temperature of the engine. Running a too cold thermostat will extend warm up times, will waste fuel, will lead to fuel contamination in the oil, and might contribute to scoring the cylinders/pistons as the fuel washes away lubrication. That amounts to a whole lot of bad for doing the wrong thing for the wrong reason.

IF you are running hot with the proper thermostat in the cooling system you have a problem with the cooling system that needs to be taken care of.

Your wife's lack of heat may be due to the distance she is driving with that craptastic 180 degree thermostat in there.

She has about a 30 min drive to and from work so and it heats up before it leaves the driveway. So I will be checking the cooling system and then swapping in a different t-stat.