Heating issues

imidazol97

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Which green coolant do you recommend for the aluminum that's different than the DexCool formulation NOW and the Prestone Mixes with All Types which is the same formulation that last time I checked the MSDS.

I'm not convinced after the initial DexCool formula change to a different oxidation inhibitor that the shrinking of the seal strips in the lower intake gaskets is anything but a design problem.

Since the vehicle has DexCool in it, for someone at home it's almost impossible to remove all DexCool to put in a complete change of another supposedly "better" choice without residual DexCool in the block or heater core or radiator. I'm thinking of the typical person using a garden hose in their driveway.

After 84000 miles, any supposed damage due to a supposed DexCool formulation flaw or gasket material design problem has already been done.

If I were the original poster, I'd look at the character of the DexCool in the reservoir tank. If it's clouded by oily sludge, then I'd do as complete a drain and refill as possible.

Be aware, I believe GM was still putting in the pellets of ground pecan shells or some organic material such as that which would expand where there was a seep and block the seep. They were and I guess still are available or can be purchased in other brand products to seal seeps if possible. (Bars leak that is a powder in a tube I believe is the same material. Probably same as supplied to GM for their pellets, in my guess.)

Poster may need be careful that a slight clouding in the reservoir tank is not from the sealer.

Either way a drain and fill with 50/50 or of pure with half distilled water can't hurt to refresh the chemicals if the original is still in the radiator.
 
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01PrkAveUltra

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2001 Buick park avenue ultra
Cooling fans come on at 212 and 225. As far as the thermostat stick with the OEM temp which is 195 degrees. If doing a coolant flush be sure to go GREEN. Dex-Cool likes to eat lower Intake gaskets.
I was going to use Caterpillar ELC where I work for them and get it at a discounted rate
 

imidazol97

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01PrkAveUltra
needs to be very careful to diagnose. I believe he's done a lot of work.

How did 001PrkAveUltra measure the temperature on the hoses? If that's an infrared
temperature sensor, I'd use those on the heater metal fittings at the firewall.

Do a test with the engine fully warmed after driving it 10-15 minutes in normal weather.
with the heater on LOW fan speed or OFF speed, check the temperatuer of the two metal
tubes with the engine running. If the heater is allowing a good flow of coolant, there should
be only a small difference in the two's temperatures. I'd guess 10 deg F. With the blower
OFF or on LOW, little heat should be extracted from the hot water in the metal heater core.

Then turn the blower to HIGH with the temperature setting calling for full heat. The high air
speed over the metal heater core should take more heat from the coolant and there should be
a little more difference difference. If the one with the cooler water coming out is cooled way down,
I would infer that means the water is not flowing through the core due to blockage. Water is staying
in the core and having more heat extracted from it.

Then after the opinion that the heater core is partially blocked or not blocked is settled,
then look further for problems.

I read that a lot of fan noise inside was noticed. Is the air coming out the floor at a good
volume for the blower speed when set on Floor/Heat? Is it coming out anywhere else?
When changing the mode flow direction to Defroster, does the air speed coming out there
seem to correlate to the flow coming out the floor vents on heat (the care likely also has some heater flow
to the rear seat area along with some to the side dash vents to clear the door windows.

If it doesn't seem to have good flow there, the problem may be the mode door actuator.

If the heater core is deemed to be good, and a problem is suspected in the mode door or
the blend door that adjusts the temperature mix of air bypassing the heater, the actuators
can be watched from under the dash while changing the demand settings from the dash
controls. You can see the rotation of the hub.

And the actuators can be taked off and the mode or blend door manually moved with the engine
and blower motor running to see if the blend door can be moved to give full heat. That
might indicate the actuator motor isn't working correctly or the electronic control isn't
calling for the right operation. The latter would indicate time for a Tech II level unit
to operate the heater through the computer.
 

01PrkAveUltra

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2001 Buick park avenue ultra
01PrkAveUltra
needs to be very careful to diagnose. I believe he's done a lot of work.

How did 001PrkAveUltra measure the temperature on the hoses? If that's an infrared
temperature sensor, I'd use those on the heater metal fittings at the firewall.

Do a test with the engine fully warmed after driving it 10-15 minutes in normal weather.
with the heater on LOW fan speed or OFF speed, check the temperatuer of the two metal
tubes with the engine running. If the heater is allowing a good flow of coolant, there should
be only a small difference in the two's temperatures. I'd guess 10 deg F. With the blower
OFF or on LOW, little heat should be extracted from the hot water in the metal heater core.

Then turn the blower to HIGH with the temperature setting calling for full heat. The high air
speed over the metal heater core should take more heat from the coolant and there should be
a little more difference difference. If the one with the cooler water coming out is cooled way down,
I would infer that means the water is not flowing through the core due to blockage. Water is staying
in the core and having more heat extracted from it.

Then after the opinion that the heater core is partially blocked or not blocked is settled,
then look further for problems.

I read that a lot of fan noise inside was noticed. Is the air coming out the floor at a good
volume for the blower speed when set on Floor/Heat? Is it coming out anywhere else?
When changing the mode flow direction to Defroster, does the air speed coming out there
seem to correlate to the flow coming out the floor vents on heat (the care likely also has some heater flow
to the rear seat area along with some to the side dash vents to clear the door windows.

If it doesn't seem to have good flow there, the problem may be the mode door actuator.

If the heater core is deemed to be good, and a problem is suspected in the mode door or
the blend door that adjusts the temperature mix of air bypassing the heater, the actuators
can be watched from under the dash while changing the demand settings from the dash
controls. You can see the rotation of the hub.

And the actuators can be taked off and the mode or blend door manually moved with the engine
and blower motor running to see if the blend door can be moved to give full heat. That
might indicate the actuator motor isn't working correctly or the electronic control isn't
calling for the right operation. The latter would indicate time for a Tech II level unit
to operate the heater through the computer.
I am taking the car in to get the coat flushed tonight or tomorrow I was going to ask is there any way or does anyone know if there is a diagnostic mode for the heater/air conditioning digital unit in this vehicle I have heard about it from other people but I didn’t know if it was a thing with Buick’s i’m asking this to see if there is a way to tell if I can figure out which blend door I need to replace.
______________________________
 

BuickGirlFromMars

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1999 Buick Park Avenue Ultra (Supercharged)
Which green coolant do you recommend for the aluminum that's different than the DexCool formulation NOW and the Prestone Mixes with All Types which is the same formulation that last time I checked the MSDS.

I'm not convinced after the initial DexCool formula change to a different oxidation inhibitor that the shrinking of the seal strips in the lower intake gaskets is anything but a design problem.

Since the vehicle has DexCool in it, for someone at home it's almost impossible to remove all DexCool to put in a complete change of another supposedly "better" choice without residual DexCool in the block or heater core or radiator. I'm thinking of the typical person using a garden hose in their driveway.

After 84000 miles, any supposed damage due to a supposed DexCool formulation flaw or gasket material design problem has already been done.

If I were the original poster, I'd look at the character of the DexCool in the reservoir tank. If it's clouded by oily sludge, then I'd do as complete a drain and refill as possible.

Be aware, I believe GM was still putting in the pellets of ground pecan shells or some organic material such as that which would expand where there was a seep and block the seep. They were and I guess still are available or can be purchased in other brand products to seal seeps if possible. (Bars leak that is a powder in a tube I believe is the same material. Probably same as supplied to GM for their pellets, in my guess.)

Poster may need be careful that a slight clouding in the reservoir tank is not from the sealer.

Either way a drain and fill with 50/50 or of pure with half distilled water can't hurt to refresh the chemicals if the original is still in the radiator.
its amazing how much crud comeso ut when flushing. i had nassstttty OEM coolant (200k miles, 20 years old) and no burning fortunately. but Ive flushed at least 5 times in total and only the last time does my coolant stay green. I had a lot of gunk in my block but now i think the only junk i still get is my aluminum radiator. the inside was so gunked when i first started cleaning. I have a small crack(no leak) on one tank so I think I may replace it just to have clean aluminum. And Im removing my condensor (ac delete) and putting a trans and ps cooler in front when I do this. My reservoir cleaned up very well, next time it should be pristine. once i get it all settled, It will prob be the coolant it will run until major repair requires losing it or the car dies.

I dont know if the issues were caused in anway by DEXCOOL, but my hoses are original and it had 200k miles... even if dexcool was perfect it was neglected far beyond any reasonable coolant life span. So I Dont blame GM, but the original owners who kept everything else maintained but that. It wasnt orange when I got it!
Snapchat-1619488031.jpg Snapchat-157396137.jpg
 

01PrkAveUltra

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2001 Buick park avenue ultra
its amazing how much crud comeso ut when flushing. i had nassstttty OEM coolant (200k miles, 20 years old) and no burning fortunately. but Ive flushed at least 5 times in total and only the last time does my coolant stay green. I had a lot of gunk in my block but now i think the only junk i still get is my aluminum radiator. the inside was so gunked when i first started cleaning. I have a small crack(no leak) on one tank so I think I may replace it just to have clean aluminum. And Im removing my condensor (ac delete) and putting a trans and ps cooler in front when I do this. My reservoir cleaned up very well, next time it should be pristine. once i get it all settled, It will prob be the coolant it will run until major repair requires losing it or the car dies.

I dont know if the issues were caused in anway by DEXCOOL, but my hoses are original and it had 200k miles... even if dexcool was perfect it was neglected far beyond any reasonable coolant life span. So I Dont blame GM, but the original owners who kept everything else maintained but that. It wasnt orange when I got it!
View attachment 28693 View attachment 28692
So I did end up flushing it and it fixed the heating issue but now I am trying to figure out why the car still gets hot while idling. It’ll go all the way up to 200 in the gauge in the cab and it’ll read 200 on the thermostat housing but both upper and lower radiator hoses will read 160. There should be a difference and why is the housing getting so hot?
 

BuickGirlFromMars

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1999 Buick Park Avenue Ultra (Supercharged)
So I did end up flushing it and it fixed the heating issue but now I am trying to figure out why the car still gets hot while idling. It’ll go all the way up to 200 in the gauge in the cab and it’ll read 200 on the thermostat housing but both upper and lower radiator hoses will read 160. There should be a difference and why is the housing getting so hot?
the housing is a cast piece of metal with a constant or near constant fresh supply of 200 ish degree liquid heating up the housing. I bet if you were driving the housing would be cooler, if idling that metal is thin and aluminum/cast iron whatever it is conducts thermal energy as most metals are decent at.(point a flame at a knife for a bit and it will be hot even a while after pulling it away. )

200 is a good reading on your DIC. Drive on a steep hill, by chance, and see if you get a low coolant warning. if you dont, then Id say you fixed your problem bud, no need to worry
 

imidazol97

Top Dog
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I'm surprised that the heater wasn't blocked enough that it wouldn't respond to a simple flush.

Did the store use a cleaner of some kind to try to remove sludge/crud?

If the heater is working, you've solved you question about the blend door.

I don't want to be a Don Downer, but if it were some blockage in the heater, don't be surprised
if the blockage returns after a while despite the flush. That's the impression I got from years of
watching the H-body forums. But I was wondering if they have a better flush product than used
to exist.

If the engine temp gauge isn't overheating...
if the engine isn't giving some boiling burps into the reservoir after shutting down after a hard drive...
Just keep on driving.
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01PrkAveUltra

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2001 Buick park avenue ultra
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the housing is a cast piece of metal with a constant or near constant fresh supply of 200 ish degree liquid heating up the housing. I bet if you were driving the housing would be cooler, if idling that metal is thin and aluminum/cast iron whatever it is conducts thermal energy as most metals are decent at.(point a flame at a knife for a bit and it will be hot even a while after pulling it away. )

200 is a good reading on your DIC. Drive on a steep hill, by chance, and see if you get a low coolant warning. if you dont, then Id say you fixed your problem bud, no need to worry
Alright thank you. The only thing I had left to inquire was the top and bottom radiator hoses are the same temperature. Is this normal? Or should there be a difference?
 

BuickGirlFromMars

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1999 Buick Park Avenue Ultra (Supercharged)
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Alright thank you. The only thing I had left to inquire was the top and bottom radiator hoses are the same temperature. Is this normal? Or should there be a difference?
ideally the outlet to engine should be colder but if you are sitting still with a temp gun you arent gonna have much difference
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Buickguy123

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Thank you, is there a procedure as far as gaining access to the blend doors?
On my 93 Park Ave one blend door actuator is behind the glove box. There are YouTube videos how to remove it. How you get to the driver's side I do not know. Both of mine are broke. Getting your hand in to get to the back screw behind the glove box does not look easy. Mine was sticking and ticking so I just unplugged it....you may have to remove the upper dashboard too? I am sure it can be done.
 

Buickguy123

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I am a new sign in to this site and am looking forward to all the help and wisdom shared here. I have a 2001 Buick park avenue ultra and I drove it home and the heat seemed like it was working properly. The temp gauge was showing 185-195 the whole drive home.(the car only has 84,000 miles so I’m assuming it had the factory 210 thermostat. Well I drove it to work with my twin the other day and it would not get hot. The temp outside was 16 and we were doing 80 down the freeway and the temp gauge only showed like 140-150. This the air never when got lukewarm. I have since replaced the thermostat due to speculation that it was bad due to it not getting hot. So I put in a 180 temp thermostat(I have always run my stuff a little cooler.) Well after that the temp thing was not fixed and I have been burping the cooking system for the last couple days and to no avail on it getting past lukewarm. I used a temp hun and checked the hoses and thermostat housing the housing was up to 190 and the hoses only showed 160 to and 140 lower. My question is do you think it is heater core?(still has factory dexcool) or a blend door problem? Also inside the cab it sounds like the blower motor is going to town and moving a ton of air but it’s hardly noticeable from the vents(I replaced the cabin air filer) I have heard of a temp switch/resistor and also of blend doors. Where are these things located? Also where would I be able to purchase them?
You are driving a 2001 and the Dex has never been changed or you are simply saying it still uses DEX cool type? If you are getting no heat anywhere in the cabin especially when in defrost mode I would think your heater core is at fault? Even if your blend doors are broke you should get heat somewhere when you put the temp at max 90. The system should default to defrost to allow the defogger to work. The window defroster at least. I am no mechanic but my advice to anybody who owns any vehicle is to replace your anti freeze every two years! Yup! Look? You put how much gas into a car every two weeks so why neglect the coolant system for years?? It is not just oil. Chris Fix has great YouTube videos on how to change the the coolant and other fluids. Dex or Green? You could do either but never mix the two brands. If the Dex is not thick or like mud you could stay with that. I buy Supertech coolant or Peak at Walmart and a gallon of distilled water there and mix em for 50 50 mix. Cheers.
 

Buickguy123

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Which green coolant do you recommend for the aluminum that's different than the DexCool formulation NOW and the Prestone Mixes with All Types which is the same formulation that last time I checked the MSDS.

I'm not convinced after the initial DexCool formula change to a different oxidation inhibitor that the shrinking of the seal strips in the lower intake gaskets is anything but a design problem.

Since the vehicle has DexCool in it, for someone at home it's almost impossible to remove all DexCool to put in a complete change of another supposedly "better" choice without residual DexCool in the block or heater core or radiator. I'm thinking of the typical person using a garden hose in their driveway.

After 84000 miles, any supposed damage due to a supposed DexCool formulation flaw or gasket material design problem has already been done.

If I were the original poster, I'd look at the character of the DexCool in the reservoir tank. If it's clouded by oily sludge, then I'd do as complete a drain and refill as possible.

Be aware, I believe GM was still putting in the pellets of ground pecan shells or some organic material such as that which would expand where there was a seep and block the seep. They were and I guess still are available or can be purchased in other brand products to seal seeps if possible. (Bars leak that is a powder in a tube I believe is the same material. Probably same as supplied to GM for their pellets, in my guess.)

Poster may need be careful that a slight clouding in the reservoir tank is not from the sealer.

Either way a drain and fill with 50/50 or of pure with half distilled water can't hurt to refresh the chemicals if the original is still in the radiator.
Both Chris Fix and Scotty Kilmer have good YouTube videos on changing and flushing the coolant. I prefer Chris Fix. Yes you can get pretty much all the Dex out and you can buy Supertech or Peak green at Walmart for 10 bucks and mix a gallon of that with a 90 cent gallon of distilled water from the same store for a 50 50 mix. You can remove the thermostat...easy...and flush the system really good. Just do what Scotty or CF does exactly.
 

Buickguy123

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I am a new sign in to this site and am looking forward to all the help and wisdom shared here. I have a 2001 Buick park avenue ultra and I drove it home and the heat seemed like it was working properly. The temp gauge was showing 185-195 the whole drive home.(the car only has 84,000 miles so I’m assuming it had the factory 210 thermostat. Well I drove it to work with my twin the other day and it would not get hot. The temp outside was 16 and we were doing 80 down the freeway and the temp gauge only showed like 140-150. This the air never when got lukewarm. I have since replaced the thermostat due to speculation that it was bad due to it not getting hot. So I put in a 180 temp thermostat(I have always run my stuff a little cooler.) Well after that the temp thing was not fixed and I have been burping the cooking system for the last couple days and to no avail on it getting past lukewarm. I used a temp hun and checked the hoses and thermostat housing the housing was up to 190 and the hoses only showed 160 to and 140 lower. My question is do you think it is heater core?(still has factory dexcool) or a blend door problem? Also inside the cab it sounds like the blower motor is going to town and moving a ton of air but it’s hardly noticeable from the vents(I replaced the cabin air filer) I have heard of a temp switch/resistor and also of blend doors. Where are these things located? Also where would I be able to purchase them?
Wow only 84000 miles. My 2000 Buick Century has just 85000. When the car was new I removed the Dex cool with green. Change the coolant and the oil as suggested. Have you had the transmission fluid changed? NEVER FLUSH IT just drop the pan and put a new filter in...you PA should go a long time!!
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Buickguy123

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Cooling fans come on at 212 and 225. As far as the thermostat stick with the OEM temp which is 195 degrees. If doing a coolant flush be sure to go GREEN. Dex-Cool likes to eat lower Intake gaskets.
The old Dex debate? Or was it a cheap gasket design by GM? When Mom bought her 2000 Century new I had a shop flush out the Dex for green. That was 85000 miles ago. No problems since and I change the coolant every two years. I dunno? I think DEX is fine if one changes the Dex like my green every two years. 24 months. This Dex cool is why GM went belly up in 2008. Telling people to go 5 years or 100000 miles before replacing a coolant. Lawsuits..burned out engines. Dumb marketing? Mechanics debate whether it is Dex or a bad gasket or both?? I just had the gaskets replaced on my 93 PA 175000 miles pre Dex green. 28 year old car nothing lasts forever. Oil oil oil? Other fluids need attention too!
 

Buickguy123

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Your factory thermostat is NOT 210 degrees, that is insanely hot. 190 or 195 was the factory hot thermostat, 180 was a cold factory thermostat. 180 is too cold for the winter unless your cooling system doesnt work right.

Are you losing coolant? You have original dexcool at 80k miles, your DEXCOOL has spent many years sitting and breaking down. Its not meant to go that long. Flush it out.

Your blend doors dont make your engine run cold, you need to confirm your engine is at the proper temp before worrying about your blend doors.

Flush your coolant, makes sure your heater core is flushed well in this, and put nice fresh new DEXCOOL or green(one or the other, not both, full flushed). Then get the air out. You have a bleeder valve on your thermostat housing and various ways to bleed air. Jacking up the front of the car so the radiator cap is the top of the cooling system is a good way. Run the car with cap off till its warm for thermostat to open, once its open youll see coolant level drop. Keep it full. Burb the hoses, etc. A no spill funnel makes this easy.

Then cap it and make sure its operating properly. Air pockets in cooling system can make your coolant read cold if the pocket is next to the coolant sensor.


Once your coolant is good, report back with any issues like interior heating
Blend doors? More mechanical to break. My wonderful 96 GM 3.1 Lumina had the best heating AC control knobs. Simple...LOL
But I would think it would stay cooler with that 180 degree thermostat in it...
 

2007LucerneCXL

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2007 Lucerne CXL. and 1995 Lesabre currently, past 1973 Riviera, 1968 Riviera
The Lumina, along with every vehicle made, has a blend door as its how that little knob with the Red and Blue markings works. Oh the Lumina also had actuators and vacuum controls, so it's the same system just doesn't have a fancy control LOL.
 
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