93 grand am has very poor heat output

[antoniobanderas]

hi,two years ago i replaced the heater core becouse of same thing,but it really didnt correct the problem ,now ,this starting winter,never the less to say,its COLD here in chicago,the porr heat output has me worried,the car will reach normal temps,around 165 or so,the radiator hose fells real hot,heck,even the radiator fan cames on once in a while ! still ,the heat inside is not eunoghf,i went to a shop and was told the heater core probably is clogged ,but i know that can not be the case since the old one,(i still have it) will floow hot water and get reall hot real quick when i put kitchen water trhu the intake,i am thinking maybe i have a blender door not closing well or something like that,if someone had this problem in his car,please share what was the problem in your case,as we all know ,tearing the dash apart to put a new heater core is no fun ,specially now well ,thanks for any input guys i will be reall thankful when i get the heat back in this 93 grand am (the tstat i assume is ok since car will reach normal temp ,just the heat is not hot like any normal car) :(

[tgussie666]

Dunno 165 seems awfully cool for a temp. I thought it was usually around 195-210 degrees. When was the thermostat changed last? I'd try that 1st since that is a cheap problem. Hope that may help.........

[antoniobanderas]

thanks for the reply,yea i agree it migth be whorth the shot,tomorrow i will see its not that easy to remove the stat ,its prrotected way too much (GM) way of job security ) but,like i said ,the radiator fan does came on ,this indicates the temp is on the mark ,sort of ,remember ,water boils at 180 d ,but since its at pressure its higher ,antifress help the boiling point toobut who knows ,by the way,in sumer heater output would olmost burn you skin way hot air but now the outside temp here in il is 45+ not too cold to give this litlle heat :???:

[4kQuad]

Next time you have ran it for a few minutes, fell the raditor hoses then feel the heater core hoses. They should all be the same heat.

If the heater core hoses are cooler than the raditor hose, then a clogged heater core might be the problem.

Else I would go with the stat.

[antoniobanderas]

today ,i replaced the heatyer core ,what a chore! it took alot of time and agravation ,the worst? the car still same as before! tomorrow i will try the stat,and keep fingers crossed ! i inspected all linkage flaps levers etc ,nothing broken or desconnected,well ,even the heater core gets reall hot ,still the output isnt strong like it shuld be ,i can imagine when the temps drop later on !! dam !:(

[nvgase]

Pull the blower motor and look at the AC core. Mine was completely stopped up with gunk and no air could get through. I sprayed it as good as I could in every direction with brake cleaner and let it set. Sprayed it again after a while and it started getting cleaner looking. I then rinsed with water the best I could and let it air dry. When you start it the first time, roll the windows down and turn the blower on high. The brake clean smell will take a few minutes to clear out. I don't remember ever having this much air flow or heat as long as I've had the car.

[antoniobanderas]

well guys ....i went trhu hell removing a bunch of parts to finallyt installing a new termostat,any better ? nhaa! same bs ! seems this car loves to run lukwarm ,the heater core i was going to replace supostly, ,was very hot to the tuch when i got acces to it ,so i did not go furhter,i put all back togheter,i think is just unother exelent bad design flaw from our loving GM ENGINEERS ho well,my nex car you bet,wont be american made ,sorry but thats the sad reallity guys

[Colin]

Make sure the heater control is opening the heater up properly , it may be stuck half open . Your antifeeze is mixed 50/50 with water right ? Too much straight coolant wil not tranfer heat properly . ( antifeeze acts like an insulator , it's the water that transfers the heat to the metal ) ;)

[swalt]

I have a 93 GT which I am the original owner. My car has never really blown all that warm....has always been that way since new.

[nathan_w1]

I feel your pain man. I got the same problem.

[antoniobanderas]

i had some of the smal hoses in the motor replaced like a cuple of months ,in the invoice they charged my for two gallons of antifriser i think what you say makes al;ot sense ,i will try dumping some and replacing with water alone ,thanks!

[rixGAphx]

Not that it helps with this heater poblem, but

Water boils at 212*F.

Since it freezes at 32*F, that's 180 degrees of DIFFERENTIAL, which is used in the farenheit-centigrade conversion.

********
GM has always been known for excellent, dependable AC and Heat.

If you don't have heat, something isn't working.

In addition to buid-up on the AC evaporator coil and the heater core, another thing to check is the air inlet to the blower box.

You should be getting a ~50-50 mix of fresh (outside) air and return (inside) air on the heat settings.
If you're getting 100% outside air, and that air is frigid, you're still gonna be chilly inside no matter how hot the heater core gets.

Good luck.
-Rick

PS: True, water transfers heat better than antifreeze, but only by about 1.5 %.
This doesn't make a difference in trying to cool a hot-running engine in the summer (I've tried, on several different vehicles), and it would have only negligible effect on heating the cabin better in the winter.
If his cabin is being warmed from 32 to 52*F (20* rise), then a 1.5% increase in heat transfer would only get (1.015 * 20 = 20.30* rise) = 52.3*F.
Not worth anything in his case, IMO.

[Colin]

Originally posted by rixGAphx
This doesn't make a difference in trying to cool a hot-running engine in the summer IMO. I'm surprised at this statement coming from you of all people Rick . Try putting straight antifreeze in the cooling system on a hot day and see what happens . ;)

[Dan]

The wife and I just return from a 5500 plus miles road trip now she has 192,plus on her
she did great average 26-27 mpg. Anyway half way through the trip we had no heat the temp is normal all fluids check okay rad hose are hot but one of the heatercore hose's seems cooler than the other. So I'm thinking clog heater core hmmm.. on a 3year old heater core maybe? When we first start up the car and let it warm up then turn the heat up we get heat for about 1 min. then cools off. Any thoughts? I'm going under today to flush out the heater core. thanks Dan

[Dan]

Well it was a clog heater core. I disconnect the heater hose's then took a gardner hose to flush it out it came out brown with junk at first, then clear water. Then reversed the flush. Give it try, now I have heat and its hot.

[rixGAphx]

Originally posted by Colin
I'm surprised at this statement coming from you of all people Rick. Try putting straight antifreeze in the cooling system on a hot day and see what happens . ;)
I'm sure that would be the shiatz!!

But I was comparing a 50-50 mix, or even 25AF-75Water mix, to running straight water.

The superior heat transfer of water only creates about a 3 degree F temp advantage, dropping the summer running temp from about 212 to 209.

Since a 50-50 mix gives a raised boiling point of about 5 degrees, the heat-transfer advantage of water is nullified.
Plus, antifreeze is the lubricating medium for the waterpump bearings.

-Rick

PS: There's a product called 'Water Wetter' that can be added to straight water, or to 50-50 coolant, which somehow increases/'restores' the heat transfer ability of water.
If it were cost-effective and had good longevity with no drwbacks, I'm sure somebody would be marketing it as an additive to regular AF, or mixed and marketed as a 'better' AF.
So, there's prolly something about it that degrades or causes other problems.

[Colin]

Originally posted by rixGAphx
I'm sure that would be the shiatz!!

But I was comparing a 50-50 mix, or even 25AF-75Water mix, to running straight water.

The superior heat transfer of water only creates about a 3 degree F temp advantage, dropping the summer running temp from about 212 to 209.
Gotcha ....;)

[zaac]

Originally posted by nvgase
Pull the blower motor and look at the AC core. Mine was completely stopped up with gunk and no air could get through.

That was my problem too. Cleaning it helped big time.

[Violator]

I remember on my 93 Skylark I had that prob for two winters, I went through 2 heater cores with no change, put in a 190 degree stat. no change. Well the cores that I bought where copper so I said lets try a aluminum. BAM!!!!!!! it worked. Hot hot hot........

But my 93 GAGT seems to blow weak air, I just purchased it about a month ago and have noticed that the blower is failling but I think its because its been gunked up for a long while. Ive noticed that the passenger side blows cooler air than the other vents. So I think that its time to clean it out, also there is a prob with water that I found under the carpert in the dampining layer. so All that has to come out :(
Anysuggestion or tips for doing this are much needed.