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1998 Taurus Heater Problems

10-25-2004, 12:22 PM
Hoping someone out there can help me! I saw the comments about the heater core, but I don't think that is my problem. Heater core has never leaked, car has never ran hot...heater core was flushed and thermostat has been changed out. Could the problem of "NO" heat have something to do with the thermostat control on the front of the a/c-heater/radio controls? :banghead:

10-25-2004, 07:30 PM
I had a similar problem and a Heater Core Flush and system flush by my Ford Dealer did help a bit but didn't get my heat coming from the vents like I thought. The highest Air temp I measured was about 140 % from the air vents. About a month ago I checked the vent air temp again and it was still about 140 % I wanted to flush the system again to see if I could get the air temp up a bit higher. I attempted to remove the heater hoses from the heater core and found the steel lines that run up the fire wall to be very rusty and broke as they were almost rusted through. I flushed the heater core and system myself and replaced the steel lines that run up the fire wall with Gates heater hose and Gates elbows to resemble the original steel heater lines. I put every thing together and gave it a try. I measured my vent air temp after going for a short ride and was very suprised to find the vent air temp was up to 173 % WOW!!!!!! Maybe just maybe it has something to do with the steel lines, maybe they are rusting from the inside and creating some resistance and there for the hot coolant is bypassing the heater core. Please let me know if you try this and if it works. The cost of about 4 feet of heater hose a box of clamps and the gates elbows and straight connectors was about 20$..........hope this works has for me so far. Maybe all the rust were all experencing in the coolant system is from these steel lines.

10-27-2004, 07:52 AM
I'm having the same problem, flushed core through those
steel lines, water went through nice, also replace my thermostat,
added fluid, it's warm but not hot air, turn fan on higher or at idle
goes cold again

my temp runs at about 1/3 to 1/2, engie really never gets hot

It almost like there is a bypass valve or someting allowing
fluid to pass even though the thermostat is closed

10-27-2004, 05:55 PM
None of you guys said what year of car you have.

Anyway I had a 94 that had the same problem.

If both sides of the lines going and coming from the heater core are hot
it is most likely the blend door actuator.

I fixed it myself and if I had to do it over again I would pay someone to do it.


10-27-2004, 06:31 PM
My Taurus is a 1999....... By the way how warm or hot is the air coming out of your heater vents? Mine is about 160 to 170 depending on the fan speed......Thanks,....ed

10-27-2004, 09:36 PM
Same problem on my 99 the heater blows cold air.
Must be a relay somewhere.
Any help/advice would be appreciated

10-28-2004, 07:48 AM
It's warm when the rpms are at 2000 or higher on the highway.
turn fan on high and get cool, at idel blow cold no matter
what the fan is set to

No sure about the temps

10-28-2004, 07:49 AM
One side was hot, the other very warm

I have a 98.

where is that valve you are talking about, is it in the 98's

10-28-2004, 05:32 PM
Found a simple fix!
In the engine compartment take the 2 hoses off the heater core where they go into the firewall and flush it out with a garden hose.
It works!!

12-18-2006, 09:56 AM
Problem was very little heat. Checking the heater core inlet and outlet temps by hand, the inlet was hot, the outlet was luke warm.

I used the garden host to back, and then forward flushed the heater core several times at the firewall and now the cabin heat is back to normal. Typically 140 to 150 deg at the dash registers. Amazing the difference! The fix worked, thanks to all!


12-18-2006, 12:58 PM
My problem ended up being a combination of crap in the heater core and a water pump with almost nothing left of the blades. Flushed the core and replaced the pump, I have great heat now. When it warms up a bit I'll flush the core again just to make sure I got it all out.

12-19-2006, 09:33 AM
Went to Ford today, found that if you ask for a pri 1999 water pump you will be given a 2000. There have been 3 service bullitins with 3 upgardes to the pump and bypass hose. The diffeance . . . my 97 pump has, by design, bent blades only, the 2000 pump has, along with bent blades, a round disk attach to the blades (something like a large washer) which I assume will make the pump a little more effective. Also the bypass hose is differant . . the hose is shorter and positioned higher up . . not sure why! I see other saying (same with me) if I rev the eng Ill get warmer air . . but I also notice If im going up hill I get hot, if im going down i get cold (both up and down under acceleration/hi rev) my conclution is gravity vis bypass hose highth might be why the new hose was changed. I have a clean core and a good pump (not the new one)but im freezing . . . it got down to +30 last night! Also i might add when i flushed the core i filed it with a full strangth flushing fluid over night then washed it out with a hose.

01-17-2007, 01:11 PM
Longwinded, but stick with it please! Had a 97 Taurus overheat and shutdown on the

Interstate about a year ago. I had run low on coolant somehow. Let it cool. Got coolant in it. Everything fine. Began losing coolant from reservoir cap later. Replaced Cap. Still losing. Replaced reservoir. Everything fine for while (six months). Radiator

develops slow leak. Flushed and stop leak put in. (Water was rust !) No help. Driven with slow leak for month (topped off twice). Radiator replaced and now something strange is happening. Sitting at a drive through the night after getting radiator replaced the temp has redlined! Shut the car off, let cool. Drive home. Now anytime I sit for 5 or more minutes the temp redlines. The fans blow fine. Once I start moving temp immediately normalizes. Even runs colder than normal while moving

for a bit and then stabilizes. What's even odder, while it's running hot, the heater

blows cold! Once I get moving the heater blows warm air. This fluctuates. Little cold,

warm. Sometimes it just blows cold while Iím driving, not enough to defrost! While driving its usually normal. The guy that replaced my radiator said it's

not the thermostat, because it would be stuck one way or the other. Both lines into the

firewall feel normal (hot,warm). He suggested a compression check to make sure it's not being lost through the head gasket, but I'm not losing coolant! Suggestions?? gonzotrek at yahoo

01-17-2007, 02:01 PM
We see the same senario many times and the water pump blades have a way of wearing down so if you try everything else and it doesn't work replace the water pump.

01-17-2007, 05:04 PM
I have a problem that I nor my mechanic can figure out. I have a 98 Taurus wagon. I was losing coolant and found out that my reservoir was leaking. He replaced it and flushed out system. He saw something unusual that he didn't know what it was. It was a brown powder type substance. He did a chemical flush on it.

I then moved to another city. My car would run very hot. I put the heat on to see if that would reduce the temperature. I barely had any heat at all which I thought was odd. (this was in the summer months) I took it in and had the thermostat replaced and system flushed.

In the fall when I needed heat I barely had any. I took it back in and he said it was probably the heater core but he was reluctant to change it because it was a big job and expensive. So he flushed it out again.

I had heat for a couple of months. Then ran into the same problem, hardly any heat. He decided to change the heater core. When he was taking it apart he found a clog. He didn't change the core he just flushed it out again and told me to see how long it lasts.

About two months later I had the same problem. Hardly any heat. I searched forums and found a problem with the water pump fins corroding and breaking away causing clogs in the system. I suggested this to him but he figured if that was the problem it wouldn't push the water through properly and cause an overheating problem.

So now we are back to changing the heater core. I wanted to ask someone before I do this if they have had any experiences like mine. My controls are manual. I don't have a leaking problem. Just a no heat problem. He can't check the water pump unless he takes it out and apart. He figures there is calcium build up in the core causing clogs.

01-17-2007, 09:17 PM
'The diffeance . . . my 97 pump has, by design, bent blades only, the 2000 pump has, along with bent blades, a round disk attach to the blades (something like a large washer) which I assume will make the pump a little more effective." I'm fairly sure the disk prevents caviation at high RPM's.

"He can't check the water pump unless he takes it out and apart."
I repeat; "We see the same senario many times and the water pump blades have a way of wearing down so if you try everything else and it doesn't work replace the water pump." Had a thread where the car never ran hot so you would not think the water pump was bad, but it wouldn't put out heat. He did everything in the book and spent a lot of money and finally when there was nothing else left to do they pulled the water pump and lo and behold the blades were worn down to a nub. New water pump and GLORY HALLEUJAH SHOUT BAMALAMA! they all the heat they wanted. :ylsuper:

If the t'stat is stuck open it will take a long time to warm up, if it's stuck closed it runs hot in a few minutes. If you take a garden hose and put it on the heater core pipe and slooowly turn up the pressure and you get good flow then the heater core is not plugged. Caution there because to much pressure can rupture the core, then you got deep pocket $$ problems. Hoses you take both ends loose and put the garden hose test on it and if water flows freely it is doubtful the hose is plugged.

After you have done everything to fix the heating problem I can not say without a doubt the water pump is bad, but when you're in a corner with nowhere else to go the next logicsl step is to do what you have not yet done, i.e., CHANGE THE WATER PUMP. (I'm beginning to sound like a broken record here,here,here,here,here,here . . . . ) :rolleyes:

01-18-2007, 07:48 AM
xJayx and cardkleener -

It is easier to keep track of problem cars if they each have their own thread, instead of hijacking a really old thread. I am confused with the number of cars needing help in this thread. It is ok to reference an old thread in a new thread, but please start your own threads in the future.

Worn waterpumps are a common occurance. I don't know what motors you have, so I don't know what would be involved or the costs to replace the waterpump.

03-22-2007, 06:28 PM
I have the same problem except when the car is running normal speed, it doesn't overheat. When I stop at a light, the gauge goes up. I don't see any leaks and also I don't have any heat or defrost at all. I just think it's weird that it gets hot only when stopped at a light while in drive. Sometimes it will get hot if you put it in Park. I can't go through Drive - throughs at all. I can't take the chance. I figured maybe the water pump or thermostat. I've all ready forked out a lot of cash and can't afford much more. Can anyone lead me to the right direction? I have a 1998 Ford Taurus Station Wagon.

03-22-2007, 07:16 PM
". . . when the car is running normal speed, it doesn't overheat. When I stop at a light, the gauge goes up." At 35 mph you have a 35 mph wind blowing through the radiator, plenty enough air flow to keep it cool. You stop the air flow obviously stops so maybe it's your radiator fans that aren't working. If the radiator itself is partially clogged then that could cause your problem. Doubtful it's the t'stat 'cause it would be partially open and they're cheap so I'd replace it for starters. Don't get a colder one than Ford recommends because your gas mileage will be less.

They make radiator flush or cooling system flush additives where you put it in the radiator and drive it around for awhile then drain and do a real good flush to get all the chemical out. That cleaner is toxic and I'd wear safety goggles. Go to a parts store and rad some of the labels and you'll see what I mean. Another way would be find a radiator repair shop and see if they can do a power flush on the radiator without removing it or at least ascertain if the radiator is doing it's job water flow wise.

Last but not least, water pump blades have a way of wearing down were they don't pump enough water so if the t'stat is good and radiator isn't gummed up I'd be looking at replacing the water pump. I doubt you can see the blades without removing it from the car.

Everything you need to know about cooling systems:
98 Taurus: "My problem ended up being a combination of crap in the heater core and a water pump with almost nothing left of the blades. Flushed the core and replaced the pump, I have great heat now. When it warms up a bit I'll flush the core again just to make sure I got it all out."

Good luck and hope all this helped. Now get to work . . . :slap:

03-22-2007, 09:41 PM
Hi All:

After my last post I took my car in and asked them change the water pump. I gave him the link for this site and he was impressed. He was hesitant at first but after reading the forum he went ahead and changed it. The car has been running great with no heat problems at all. He also called a friend of his at Ford and was advised to flush the rad and change the coolant from red to green. SO go ahead and do the pump and change the coolant after a good flush. It worked for me and others on this site.

03-22-2007, 10:17 PM
Red coolant: I assume that is GM's DexCool also known as DeathCool. For goodness sakes, don't ever put in any vehicle unless it would void the warranty. Stick with tried and true green stuff like Prestone and you're good to go. Glad you got it fixed and hope main51 gets theirs fixed as well. Always appreciate folks telling us we helped them solve the problem because we don't get feed back from everyone. :boink: It's late and I'm a tired old Geezer, so G'nite all.:sleeping:

08-29-2009, 03:37 PM
I have a 1999 Ford Taurus, that the heater doesnt work every winter. Don't be told you have to replace the heater core unless its leaking. I have some help since I have been fighting this problem a long time. First of all flush the heater core with Simple Green. I pour it down in heater core with funnel and let is sit for about 40 min and flush out and repeat, Simple Green will not hurt anything like acid or drain cleaner will. After the second 40min with Simple green flush with water hose or hot water from your water heater, flush back and forth until clean. Next flush the radiator and engine with Simple Green, after you get the engine flushed. I put a small hose clamp with wire on one of the heater core inlets and attach the other end to firewall so its grounded to stop the electric current from causing rust build up in heater core, then reattach hoses add new antifreeze and heater works fine. After about 3 months, I reverse the heater core hoses so it reverses flow in the heater core. If I see any browning of antifreeze I flush with Simple Green. I usually now can go 8 months without flushing heater core, Ford ought to address this problem but they told me they have never heard of it but I told them of a TBS and they said they would look it up. Well now I don't have to worry, I have a great heater in the winter. I hope this helps some.

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