Heater not working

are you certain that your cooling fans are turning on when the car is reaching the proper operating temperature.

This guide will help

https://www.2carpros.com/articles/car-heater-not-working

[quote:e8c7219076="blackop555"]are you certain that your cooling fans are turning on when the car is reaching the proper operating temperature.[/quote:e8c7219076]


only seem to come on when i turn control to a/c

ok check your relay or hardwire it to stay on and see if it works just fine. Also change your radiator cap, and see if that stops the overheating and bubbling problem.

and for the heat problem feel the heater core hoses when there is no heat and let me know if one hose is hot, no hoses is hot, or both are hot.

What could be the problem? The air blows but it never warms up when you have the heat on. Is there an easy fix for this?

It sounds like the electric actuator for the heat blend it not working. There are two actuators and the right one is the one I suspect to be non operational. Or your heater control valve is stuck closed.

We have a 99 chevy Lumina 3.8 Litre engine. The radiator was replaced 18 months ago and upper and lower radiator hoses and thermostat were replaced about 5 months ago. Now that it seems to be getting cooler outside the heater is blowing luke warm to cool air at operating temp. We also noticed some steam or smoke comming from the front driver side which looks like it is comming from underneath the hose leading to the thermstat. Coolant level is fine in the reservoir and radiator.

Hi:
If you had the hose replaced, check to see if it's tight. Also, mak sure the t-stat housing is tight.

The heater is another issue. The heater core may be plugged. One easy way to check is to locate the heater hoses under the hood. There is an inlet and outlet. With the engine running at operating temp and the heater on, feel both hoses. One should be VERY HOT and the other just slightly cooler. The hottest one is the inlet. The SLIGHTLY cooler one is the oitlet. If the outlet is cold or MUCH cooler than the inlet, it sounds like the core may be partially plugged and need replaced.

NOTE: THE HEATER HOSES HAVE THE POTENTIAL OF REACHING TEMPS. OF OVER 200 DEGREES. BE CAREFUL!

I hope this helps. If you have any other questions, let me know.

Joe

Thanks for the response. My thermostat was bad I replaced it and BAM all working again.

I have a 1998 Chevrolet Lumina with a 3.1. At the end of last winter the heat was on whether the heat control was set to cold or hot. Then suddently it only blew cold air no matter where heat control was set. Now it is winter again and still blows cold air. There is no overheating problem, the heater hoses are both hot, the fan works fine, the climate controls work fine, vent, bi level, defrost, etc. It just blows cold air, I read about temperature control solonoids and actuators that control the flow of heat into the car, where would these be located? Or is it something else like the thermostat?

try pulling hvac fuse first for 60 seconds with key on then reinstall it may reset actuators. not knowing if you have dual zone you may have two of these. also check for a vacuum leak start at engine and work through heater/

As it turned out it was the electric actuator or the lack there of one. I am wondering if a certain repair shop didn't remove it in an attempt to get some money out of me. I discovered this by going to a junk yard and finding a car just like mine and examining the heater box on that one, mine was certainly non-existent only a dangling wire. Can you believe that? It just goes to show find a good pull and pay junk yard and do the troubleshooting yourself.

well I don't know the circumstances and if it were owned by aprevious owner that may have been done to make the a/c work. but there are unscrupulous people out there.

Engine Cooling problem
1998 Chevy Lumina 6 cyl Automatic 102000 miles

3 weeks ago replaced themostat in car because of no heat. Car ran great until this weekend. Low coolant light came on. Added antifreeze. Car temp immediately went sky high and heat quit working inside car. Found a small hose around thermostat that was unclamped. Reclamped, still temp running high and no heat. Coolant full, will not take anymore. What might be the problem?

If the t-stat is new and the coolant is full, either you have a plugged radiator or blockage in the engine. Check this. With the engine running, warmed up, and the heater on, feel both heater core hoses. Both should be hot.

Let me know what you find.

Joe

The heater will take like 30 minutes to heat up. It will then blow warm air for any random variation of time could be a minute could be an hour. And it will be bursts of cold air... It almost as if it is switching from hott air and cold air randomly... Not great with cars but know a little... Any help is appreciated, and please explain throughly. Thanks

Is your engine slow to warm up?
If so, your thermostat is stuck open and you'll need to replace it. One way you can check it is by turning on your car, and feeling the upper hose with your hand. There should be no coolant going thru this hose until the car is at normal operating temperature.
If you feel coolant going thru the hose as soon as you start your car or before your car reaches normal operating temp, you know your thermostat is defective.

If your thermostat is OK, it's likely one of the following:
- low coolant level
- Clogged heater core
- defective heater valve
- vacuum leak

Replaced therm radiator and waterpump. Heater blows cold air temp rises and car overheats can u tell me wht I can do to stop overheating and gt heat

You may have air in the coolant system.
To bleed it allow the car to cool and remove the radiator cap. Turn the heater setting all the way hot. Allow the car to reach operating temprature and then top off radiator and reserviour with a 50/50 mix of anti-freeze and distilled water.
Also replace the radiator cap.

Replaced thermostat waterpump and radiator. I bled the system. When I drive the car temp rises an heater blows out cold air. No water mixing with oil so what could keep causing car to overheat

Need more information engine size, are you sure the radiator fans are working, do you have the thermostat installed properly? These enegines take a long time to bleed air out of the system. If all these are correct, you may have a blown head gasket, leaking into the cooling system. What exactly was the car doing to start with, no heat or overheating and no heat, leaking water. You will have to be a little more specific. Thanks for using 2CarPros

It was leaking water frm radiator 3100v6 ls

Engine Cooling problem
1996 Chevy Lumina 6 cyl Front Wheel Drive Automatic

the temp gage in the car says it hot and the top hose on the radiator was steeming and where is the themostat

you either have a leak or a bad thermostate if you work on ur own car then u might start by dumping in antifreeze and running the car to see where it's leaking and if it's not leaking then replace the thermostate.

start with what makaveli says, if you cant find the leak, then trace that top hose it will attach to a metal housing with 2 or 3 bolts holding it on, the thermostat is in there. if you coolant dont get low that quick or smells burnt then its your thermostat stickin shut. after you change the thermostat and refill the coolant you might have to bleed out the air. there should be a small screw on the thermostat housing, on one of the lines comming from the heater core, by the water pump, or all 3. with the car running open all the screws you find untill you have a solid stream of coolant come out. if that dont work check your water pump, with the car running squeeze the big hose coming off the pump(that runs into the bottom of the radiator) you should feel a surge of water if you dont your pumps bad, if you do do the same to the top hose, if you dont feel it there you might have a cloged radiator, reverse flush it. hope it helps

My temperature gage gets up maybe 1/8 or sometimes 1/4 past the half way mark. And I have noticed my fan does turn on(although my 2nd fan never turns on) but when I am in idle or when I am sitting in traffic my car starts to get hot but doesn't overheat. I am completely puzzled as the low coolant light has been on all winter as well but the coolant has never actually been low. So with that I have people telling me the sensor could be bad. And then just today the Service Engine soon light came on so Now I am completely worried and ready to figure out what could be wrong with my car. I can give more details if needed.

with the coolant level sensor throwing the light on and with the fluid level being good chances are the sensor is bad or the wiring for the sensor is bad.

check engine light is pretty major. get the vehicle scanned with a code reader. could be why vehicle is running warm or nothign related at all. but anyways autozone with scan the vehicle for free. post the code back in p***** format

I replaced all all relays & fues located down by heater. heater still will not blow. checked blower and blower is good. but controls will not make heater blow

Supply direct 12 volt power to blower motor. If motor works then suspect faulty control switch.






Thanks for using 2CarPros.com!

Heater problem
1992 Chevy Lumina Automatic 167024 miles
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we've replaced the heater core, the termostat, the switch, and checked and rechecked the vacuum lines. the antifreeze/coolant level hasn't gone down, you can hear the water circulating, and you can't smell antifreeze. The car doesn't overheat, but it just blows out absolutely COLD air. Can't figure it out. If there were a blown head gasket could that do this?

Check the blend door actutor, it could be non functional. It's on the heater plenum, disconnect the actuator, see if you can move it by hand....lubricte the shaft...

I have a 1990 chevy lumina car ...now a year ago my heatercore went out i didnt have the money to replace it so we had it rerouted so we could still drive our car. Well we got the heater core and had it put in but no heat! We tried changing the thermostat still no heat so we replaced the water pump.. radiator and Heater hose yet still no heat it comes out luke warm on days the sun is out but other than that nothing! And It isnt really pushing out the air at times either so i am thinking it may be my blower but wouldnt i still feel some kind of heat seeing how it is pushing out the cold air. So I Am stumped as to what to do next any help will be apreciated...

I've been here before-blower coming On no heat-it turns out that the blower fan is freewheeling-instead of moving at the same rpm with the motor.

Could also be the aix mix/blend/mode doors not opening due to actuator/vacuum problems

I have a 1990 chevy lumina apv van , I added bars leak into the radiator and now I have no heat, I replaced the heater core and the thermostat and I still have no heat, whats next?

Before you replaced the core you should have thouroghly flushed the Barrs leak from the cooling system, Heater cores are not built like radiator, radiators have rows of piping which make the coolant travel horizontally from top to bottom. Heater cores are built like a bee hive so the coolant disperses out ward so it stays in the core longer thus providing the heat. But it also clogs easier than a radiator because of it's design. You may have a new clogged heater core due to this fact! carefully feel the heater hoses, are they both hot? If one is cooler than the other, You need to flush the core, or do a replacement job on the heater core. Also if the system has a heat control valve on the heater hose, make sure it is working! Also check the thermostat, and the temperature blend door, thats under the dash, in the heater plenum...

Heater problem
1990 Chevy Lumina V6 Front Wheel Drive Automatic 190000 miles
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I have a 1990 Chevy Lumina 3.1 I have no heat the blower blows but does not blow hot air my coolant is fine and the engine temp is at normal operating temp. Is it the heater control valve and where is it?
Not sure if it is related but the day it started blowing cold i parked on a slope meaning the passenger side of the car was higher than the left when i ran into the store and came back out it was blowing warm and was fine the rest of the day the next morning it went back to blowing cold.

This one sounds like an air bound system. Try removing the radiator cap and squeezing the upper radiator hose while it warms up, once you see the antifrwwze circulating in the recovery tank, make sure it's full then cap it. Here are the TS charts from chevy, this could also be a clogged core!