BmoreCherokee

Replaced Thermostat, and did a full flush back in the fall. Had heat during the chilly fall mornings. Now we've had a cold spell during the past few weeks. Temps in the high 20's at night. Turn the heat on, and all I get is cool air.

Any suggestions?

crzypj

Just last week same thing happened to me. turned out to be the heater control valve was sticking. $15 at autozone. good luck!

BmoreCherokee

go figure! think you may have a solution, and they go and change the design

crzypj

well since my suggestion didn't help i figured i'd look around for you. this is a link i found on jeep forum. good luck
http://www.jeepforum.com/forum/f11/9...e-heat-636489/

JeepFan

What does your temp gauge read when it's warmed up? If it's stays below the "normal" range, then your thermostat is stuck in the open position. I had a new thermostat (2 months old) stick open which meant no heat.

rstone

Is the coolant circulating? Just replaced my rad, water pump etc but the problem was the water pump! impeller fins were rusted completely off! Pump was turning but no water was circulating...

tjwalker

*There is no heater control valve on a 99. That went away a few years prior

*As mentioned, what is the coolant temp gauge reading on the dash? Target is 200-210.
Cab heat is simply a byproduct of engine heat

*The heater core can become clogged, keeping heat out of the cab. Backflushing it both ways with a garden hose can sometimes restore function

*Be sure the HVAC blend door that routes the heat into the cab is working properly

99PurpleHaze

To OP, did you solve your problem, and if so, how? I'm having the same issues with my 99'....