I have a 92 Deville and my heater just flat out quit. i have put coolant in and also changed the thermastat. I looked into the radiator while car was running and it looked as if the coolant was flowing fine and didnt seem like it was the waterpump.
i was told to replace the htr core but also i think the waterpump may be bad too,because after driving around town only sometimes the coolant temp light comes on for a short time and turns off. So i am guessing the water pump is weak. The reason i ask is i want to fix the right thing first instead of just replacing every thing and find it was only onething that was a problem. If anybody has any ideas or had this problem, please help asap i would greatly appreciate it cause its getting pretty chilly in here and i hate to work on it outside in 25-35-degree weather[&:].

 

also i wanted to know how to get to the htr core, ihavent checked but i think its behind the glove box. i just want to make sure.

 

if this helps anyone help me figue this problem pls reply, im also having my "coolant temp light come on" but my coolant doesnt feel hot its just warm. and i have a small leak on the driver side near the bottom of radiator, i leaves about a 3 in. diameter puddle not very big but enough to notice. could this be a heater core problem that is causing this if the htr core is pluged.

 

Hey there 92_ : When you say your heater just flat out quit, do you mean the fan motor doesn't work either or just noheat from the vents???? If the fan motor is part of the problem then the heater core won't be your solution, so please clarify.

 

sory i meant to put that inthe first reply b4 , yes the fan motor works, what happened is that it only blows cold air i tried to put the heater on different tempratures since its all digital and it blows out colder air on lower settings just as it should but nomatter how high of temp. i select it blows cold air. i think i metioned everythig that i could think of.if that may help. the only reason im leaning twards the htr core is that my coolant seemed to be dirty and some one told me to take out the htr core and reverse flush it. and try that.

 

It sounds to me like two different problems. You have a coolant leak on the drivers side near the radiator; find where that's coming from and fix it because it's what's causing you to overheat most likely.

The Heater sounds more like a HVAC vac*** operated door that got stuck. When the heater is on, it should shift to the window vents and floor vents so as to not blow hot air into your face. If it doesn't shift to those vents, you wont get any hot air at all.

 

well the air does come through the floor vent and defrost vent and alsowhen i adjust the temp to a lower temp it will blow through the dash vents (usualy around 60-70degres when set).