Heater stopped working
Heater stopped working
I drive about an hour and a half each way to work in a 1990 camaro rs V6 and about a week ago my heat stopped working , the vents only blow out cold air now , no matter what , checked the anti-freeze in the radiator and in the tank and both are full , any suggestions? im freezing my butt off.
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Joined: Jan 2001
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From: Someone owes me 10,000 posts
Car: 99 Formula
Engine: LS1
Transmission: T56
Axle/Gears: 342
What has the temp gauge been reading. I would think even with it being stuck open, that the cooling temp would reach at least warm enough to blow out some warm air. A way to test the thermostat is take it out and see if it's stuck open. Of course I would just go ahead and buy a new one, they're only like $7. It's located at the front of the manifold, the upper radiator hose leads to it.
Are you sure you have enough anti-freeze mixed with the water? It's possible that the liquid in the heater core is frozen. Just a thought. Also possible that a foriegn object is plugging the core. You should be able to feel if the thermostat is working through the main coolant line ie., pressure and temperature. Have fun
Last edited by John+91'Z_4ever; Feb 27, 2002 at 07:16 PM.
Bitte...
Remove the radiator cap at the right front corner of the radiator and check the level. It should be full of coolant mix. This should ONLY be done after the engine has cooled. You should also check the level in the coolant overflow reservoir. The mixture should be at least at or slightly above the "FULL COLD" mark embossed in the plastic tank.
If the levels are correct, the temperature gauge on the dash should indicate just under 200°F when the engine is warmed up fully. If that is the case, the coolant is flowing and the thermostat is probably operating correctly. If the coolant temperature never rises much above 100°F, your thermostat may be stuck in the open position.
If coolant temperature is normal, you may have either plugged a heater core, or your hot water valve is not opening when the controls are placed in the "HEAT" position. The hot water valve is located along the right side of the engine compartment, and is spliced into one of the heater hoses. The valve also has a vacuum operated actuator that controls the position of the water valve. Start the engine and remove the small vacuum line from the water valve. Turn the heater controls to full hot (fan speed doesn't matter) and check for vacuum at the small hose. If you feel no vacuum from the small control hose, the ported vacuum switch in the dash probably needs some attention. If there is vacuum present, reinstall the small hose while the engine is still running. As you do, you should see the linkage under the valve move to open the valve. If this doesn't occur, your water valve is probably stuck or damaged. You can "help" the valve open manually. Once you get the valve opened you should be able to feel heated coolant running through the hose (and hot air from the vents in the car). If the valve will not stay open without you helping it manually, the vacuum unit on the valve is damaged and requires replacement. You can temporarily hold the valve in the open position with wire, tape, wire ties, etc. until you get a replacement valve. It won't hurt a thing unless you leave it that way until the air conditioning season arrives and you can't get cool air.
If the valve is open and you still get no heat or hot coolant flow, you either have a severely corroded cooling system with serious blockages, of the heater core is plugged with debris and corrosion.
Let us know at that point.
Remove the radiator cap at the right front corner of the radiator and check the level. It should be full of coolant mix. This should ONLY be done after the engine has cooled. You should also check the level in the coolant overflow reservoir. The mixture should be at least at or slightly above the "FULL COLD" mark embossed in the plastic tank.
If the levels are correct, the temperature gauge on the dash should indicate just under 200°F when the engine is warmed up fully. If that is the case, the coolant is flowing and the thermostat is probably operating correctly. If the coolant temperature never rises much above 100°F, your thermostat may be stuck in the open position.
If coolant temperature is normal, you may have either plugged a heater core, or your hot water valve is not opening when the controls are placed in the "HEAT" position. The hot water valve is located along the right side of the engine compartment, and is spliced into one of the heater hoses. The valve also has a vacuum operated actuator that controls the position of the water valve. Start the engine and remove the small vacuum line from the water valve. Turn the heater controls to full hot (fan speed doesn't matter) and check for vacuum at the small hose. If you feel no vacuum from the small control hose, the ported vacuum switch in the dash probably needs some attention. If there is vacuum present, reinstall the small hose while the engine is still running. As you do, you should see the linkage under the valve move to open the valve. If this doesn't occur, your water valve is probably stuck or damaged. You can "help" the valve open manually. Once you get the valve opened you should be able to feel heated coolant running through the hose (and hot air from the vents in the car). If the valve will not stay open without you helping it manually, the vacuum unit on the valve is damaged and requires replacement. You can temporarily hold the valve in the open position with wire, tape, wire ties, etc. until you get a replacement valve. It won't hurt a thing unless you leave it that way until the air conditioning season arrives and you can't get cool air.
If the valve is open and you still get no heat or hot coolant flow, you either have a severely corroded cooling system with serious blockages, of the heater core is plugged with debris and corrosion.
Let us know at that point.
Last edited by Vader; Feb 27, 2002 at 09:29 PM.
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well , lets hope its just the thermostat , my engine runs at about 240 after driving for about a half an hour, if its not the thermostat it sounds like i have a heck of a job on my hands. oh well , just hope i dont mess anything else up in the process of trying to fix this. thanks for the info =)
Originally posted by Damion
well , lets hope its just the thermostat , my engine runs at about 240 after driving for about a half an hour
well , lets hope its just the thermostat , my engine runs at about 240 after driving for about a half an hour
Eric
someone here was telling me that it isnt the thermostat and its prolly the heater core , wouldnt i still get economy heat if it was the heater core? (economy heat non ac on a 90 camaro blow heat off the engine if i remember correctly), man , so many things wrong with this car so little time and money. should i even bother changing the thermostat?
well , i got the thermostat , cuz i dont feel like ripping off my dashboard to replace the heater core , so hopefully this will fix it , ,either that or the valve you were talking about , il check that out while im out there , wish me luck!
Damion,
Put down the thermostat and back away slowly.
With that kind of coolant temperature you should be getting a LOT of heat. Either the heater core is plugged, or the hot water valve isn't opening. Since you'll have to play with the valve to do the heater core anyway, why create any more aggrevation? Check the valve first. If the heater hose is not hot on both side of the valve, you have a flow problem. Plugged heater cores are rare, and they usually leak first. I just added that as another possible explanation of your problem.
Incidentally, all interior heat is generated by air passing through the heater core, whether in the "economy" heat position or any other position. Hot air should never be drawn from the engine compartment and cars haven't been designed that was since the air-cooled Corvairs and Volkswagens left the planet.
Check the valve.
Put down the thermostat and back away slowly.
With that kind of coolant temperature you should be getting a LOT of heat. Either the heater core is plugged, or the hot water valve isn't opening. Since you'll have to play with the valve to do the heater core anyway, why create any more aggrevation? Check the valve first. If the heater hose is not hot on both side of the valve, you have a flow problem. Plugged heater cores are rare, and they usually leak first. I just added that as another possible explanation of your problem.
Incidentally, all interior heat is generated by air passing through the heater core, whether in the "economy" heat position or any other position. Hot air should never be drawn from the engine compartment and cars haven't been designed that was since the air-cooled Corvairs and Volkswagens left the planet.
Check the valve.
With temps that high it could also be your water pump. I had the same problem. If the pump is not pumping water through the core you will not get heat. This would also explain your high engine temps. Also with the shutoff valve i belive you want to have no vacuum going to it for it to run water through the heater core. On my v6 fb i hooked up a constant vacuum to the valve and lost all my heat. I belive vacuum is only sent to the valve when the temp is set completely to cold.
well i put down the thermostat, because i dont have a long enough torque wrench to get at the damn thing. i wasnt able to find the hot water valve you guys are talking about , i checked on the right side of the engine compartment and didnt see anything leading from the radiator (thats where it comes from right?) ok stop laughing , im new to this whole owning my own car to play with thing. oh and since im posting i noticed a buzzing noise coming from the general vacinity of where the spark plugs are on the right side of the engine compartment when i rev the engine, sounds like a damn alarm clock or something *shrug* , oh and my altenator is squeeling. back to the subject , the radiator hose is hot , so coolant is going through there. As far as wether or not it is reaching the engine , i dont know. found out the price of the heater core , ,not bad only 20 bucks , but ive heard its a real pain in the *** to change. so...someone explain to me in very very simple terms, how do i check the hot water valve to see if its opening?
thanks a bunch for the help so far guys , your great =)
thanks a bunch for the help so far guys , your great =)
I believe by "right side of the engine bay" he means the passengers side... that is where the heater core is...
Look on the passengers side of the engine... between the engine and the tire well... you'll see heater hoses running along a "base" kind of thing... almost a floor... then they reach the firewall and curve up and then enter the firewall right below the top of the engine bay... these are your heater core coolant hoses. Trace those hoses in the engine bay until you get to a funky looking thing that is spliced into them... this should be that hot water valve Lord Vader was talking about... from there you're on your own...
In my car, coolant flows through the heater core constantly... the heat is controlled by what the air is passing through in the dash... at least I think thats the way it works because I don't have a water control valve...
Look on the passengers side of the engine... between the engine and the tire well... you'll see heater hoses running along a "base" kind of thing... almost a floor... then they reach the firewall and curve up and then enter the firewall right below the top of the engine bay... these are your heater core coolant hoses. Trace those hoses in the engine bay until you get to a funky looking thing that is spliced into them... this should be that hot water valve Lord Vader was talking about... from there you're on your own...
In my car, coolant flows through the heater core constantly... the heat is controlled by what the air is passing through in the dash... at least I think thats the way it works because I don't have a water control valve...
Xeno,
You an me both. I think the water valve appeared on 'F' cars in '87 or '88. Mine works fine with full flow constantly (his would, too).
Damion,
If the upper radiator hose is warm, the thermostat is opening at least enough to be passing coolant to the radiator. Forget about changing the thermostat for now - that isn't your heat problem.
Trace the hoses on the right side as Xeno outlined. There should be hot coolant running through the hoses (and valve) with the engine running and the controls in the HEAT position. If not, operate the valve by hand and see what happens. Read back through the other posts for the rest. You can either wire the valve open or bypass it with a short piece of pipe or hose mender (the old system flush 'T's work well for this).
You an me both. I think the water valve appeared on 'F' cars in '87 or '88. Mine works fine with full flow constantly (his would, too).
Damion,
If the upper radiator hose is warm, the thermostat is opening at least enough to be passing coolant to the radiator. Forget about changing the thermostat for now - that isn't your heat problem.
Trace the hoses on the right side as Xeno outlined. There should be hot coolant running through the hoses (and valve) with the engine running and the controls in the HEAT position. If not, operate the valve by hand and see what happens. Read back through the other posts for the rest. You can either wire the valve open or bypass it with a short piece of pipe or hose mender (the old system flush 'T's work well for this).
I agree with Jersey, I would take the 5 minutes it takes to take the cap off the radiator, start the car, and look in the radiator to ensure fluid flow. So you know the pump is ok. I had the same problems you're having and in my case I had a worn pump. You can also check the weep hole on the bottom of it, it leaks when the pump is worn.
well, as i said , the radiator hose is hot when the engine is running , so beleive there is coolant flow. when i take off the radiator cap and let it run , is the fluid level supposed to drop? because its not dropping , and the hot water valve that im supposed to be looking for , ,is it close to the firewall? thanks =)
With the cap off and the engine running you need to wait until the engine warms up and the thermostat opens. You will know when the 'stat opens because the coolant will start flowing inside the rad (also watch the temp guage)
If the coolant level suddenly drops and you can see the interior fins of the rad then you don't have enough coolant in the system... add some
If the coolant starts bubling and overflowing into the bucket you put under the car (save a cat right?) then your water pump is working well enough that I would rule it out for the moment and head on over to the water valve
If the coolant just sits in the rad and doesn't move or circulate then I would say the water pump is bad and needs replacing
If the coolant level suddenly drops and you can see the interior fins of the rad then you don't have enough coolant in the system... add some
If the coolant starts bubling and overflowing into the bucket you put under the car (save a cat right?) then your water pump is working well enough that I would rule it out for the moment and head on over to the water valve
If the coolant just sits in the rad and doesn't move or circulate then I would say the water pump is bad and needs replacing
The top hose will get hot even if the water pump isn't working. there will be limited flow even though the pump isnt working. Hot rises and cold will fall. As many people have said warm it up with the cap off. Once it is warm open the thottle a bit and see if there is any coolant flow. Another way to check(not enviromentally friendly though) Pull the heater hose off the water pump right where it goes into the hot water valve by the pass side fender, and have someone start it up. If coolant shoots out with the engine running you know its good. Let us know what it turns out to be.
Well , started it up , throttled it a bit , let it run for a while and nothing came out , fluid level didnt drop either. No overboil , no over bubbling , so i guess its the water pump. Would that cause my heat to stop working? what about my fan?, Prolly not the fan. So i guess i need to take it to a shop and have them replace the water pump , not too expensive for the part , work charges are gunna kill me tho. Il let you guys know if it fixes it , wont be able to afford to have it fixed for another two weeks, maybe if i sell my laptop? heh. i need heat.
anyone have a diagram as to where it is located, where the bolts are that hold it in ect?, if its easy then il just replace it myself , oh yah , and will collant leak out while im changing it , big factor , would be working in a community parking lot. =) (forget saving a cat , save my *** from bbeing kicked out! =P)
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