No heat?? bad thermostat?

[HossV6]

since i bought my car in july i havent needed to use my heater until yesterday, it just blows cold air. i have noticed that my temp. guage doesnt move on cold days, on hot days it will move, so i know the guage works. could my thermostat be bad and stuck open? its getting cold outside and i still have to drive the car till the end of october. so i would like to get the heat working. Also my AC doesnt work, im pretty sure it needs charged, if i turn it on it makes a kind of growling grinding sound, i think its due to low charge, i put a small amount of recharge in it and the sound lessened, but i didnt have enough recharge left in the bottle to completely fill it, the problem is, when i go to turn on my windsheild defrost it turns the compressor on even if i have the temp knob turned to hot. is this normal? will the compressor always turn on with the defrost?

[nimrod.sixty9]

Re: No heat?? bad thermostat?

when i go to turn on my windsheild defrost it turns the compressor on even if i have the temp knob turned to hot. is this normal? will the compressor always turn on with the defrost?

Sounds like your problem to me...

Maybe knob needs adjusting, there is a site that tells you how to do it. Ill go find it now.

Here you go: http://www.xse.com/leres/ss/hacks.html
Click on "HVAC Cable Adjustment"
Hope this helps GL!

[CDNFB]

Re: No heat?? bad thermostat?

my windsheild defrost it turns the compressor on even if i have the temp knob turned to hot

This is normal. It will do this for defrost and also for the Floor/Defrost setting.

The compressor will not engage in these settings only when it is really cold out. With cold ambient temps the system pressure drops, the PCM sees this via the A/C system pressure sensor and will not engage the compressor. The reasoning behind this is that below certain temperatures, the the air being brought in is dry enough for the defrost to be effective.

As for your engine temp problem. Maybe the engine is at proper temp and you indication system is nuts. First I would confirm that it is indeed a heat issue and not just an indication problem. When the car is as hot as you can get it, have someone plug a scanner into it and read the real time data for coolant Temps. Or use a thermometer (those handheld infrared ones are cool for things like this) and measure the temp of the thermostat housing.

I had an 88 Olds that had no heat comming from the heater, but it was because the heater core was replaced and the sealant around the core was not put back, and all the cold are was flowing around the core and not through it. Maybe same for you?

[HossV6]

Re: No heat?? bad thermostat?

This is normal. It will do this for defrost and also for the Floor/Defrost setting.

The compressor will not engage in these settings only when it is really cold out. With cold ambient temps the system pressure drops, the PCM sees this via the A/C system pressure sensor and will not engage the compressor. The reasoning behind this is that below certain temperatures, the the air being brought in is dry enough for the defrost to be effective.

As for your engine temp problem. Maybe the engine is at proper temp and you indication system is nuts. First I would confirm that it is indeed a heat issue and not just an indication problem. When the car is as hot as you can get it, have someone plug a scanner into it and read the real time data for coolant Temps. Or use a thermometer (those handheld infrared ones are cool for things like this) and measure the temp of the thermostat housing.

I had an 88 Olds that had no heat comming from the heater, but it was because the heater core was replaced and the sealant around the core was not put back, and all the cold are was flowing around the core and not through it. Maybe same for you?

im almost postive the temp guage is correct, about 2 months ago i had a freak problem, my car puked out a bunch of coolant on the way home from work, the temp guage went way up due to low coolant causing it to run hot, lucky for me my buddies dad has a shop right off my exit home so i stoped in and he looked at it, he thought the thermostat got stuck closed, he had a digital lazer temp gun and he ran it over the motor and the reading matched the guage in my car, he topped it off with coolant and the problem hasnt happened since. as far as the heater box im really hoping that isnt the problem, but if it is how hard are they to get to in our cars? mine is a 95 3.4.

[nimrod.sixty9]

Re: No heat?? bad thermostat?

Isnt what I posted still possible. Maybe the temp dail is not actually turning to heat because of the cable.... Possibility?

"Over time my HVAC temperature control knob would bind when attempting to set it to full heat."

[CDNFB]

Re: No heat?? bad thermostat?

Isnt what I posted still possible.

Yes nimrod, yours is a possibility because even with very little engine temp showing on the indicator, the heater should be producing some warm air. I would definitely check to make sure the heater control door was properly positioned.