94 Taurus heater problem

[rusted and busted]

I've read many of the posts on here about the Taurus and Sable heaters not working and just blowing cold air but every post I've come across was for '96 and newer. I have a '94 with a 3.8 and only has 75,000 miles and I have the same problem. I purchased the car a couple weeks ago after it was in a light front end accident. I now have the car back together (radiator and electric fan were replaced). and cant get any heat. I was told that the thermostat and antifreeze was changed last fall (no mention was made that the heat wasn't working). After the car warms up, the temperature gauge goes up to the high end of the 'normal' scale and the drops all the way down and then slowly climbs back up again and will do the same thing again. I don't think its the thermostat because the top radiator hose gets hot. I'm thinking it might be a plugged heater core but I'm not very familiar with this car yet and any input would be appreciated.

[shorod]

Since you've put in a new radiator and the gauge is acting goofy, along with poor heat, I'd suspect first that you have an air pocket in your system. I think your '94 has an air purge/burp valve on it.

-Rod

[Frank2383]

That is possible that it is air and I would try that first. As for the heater core you can check the heater core by disconnecting all the hoses from it and connecting a garden hose to it and run water thru it to try to unclog it.

(You will find out real fast if your heater core is bad that way too. Someone might of put some sealent to clog it up, cause of it leaking. That is why it seems cloged and if you flush it out you might have to replace the heater core. Check you floorboards while doing this to make sure your not flooding your car with the water. Just in case your heater core is bad.)

[rusted and busted]

I didnt see any air purge on the engine. I'm thinking if I remove the heater hose by the thermostat and add coolant till it starts to come out it might remove the air pocket.

I just tried flushing the heater core with a garden hose and the water came out clean. So I don't think the heater core is the problem now.

[Frank2383]

I would just replace the heater core. But that is just me.

[rusted and busted]

Originally Posted by Frank2383

I would just replace the heater core. But that is just me.

I would replace the heater core too but Ford made that near impossible. From what I'm hearing its an 8-10 hour job for someone that knows how to do it. The car only has 75,000 miles on it and the previous owner changed the coolant every couple years.

[tripletdaddy]

The first won't work and I wouldn't do the second. Without removing the thermostat, you won't be able to get anything into the engine thru the upper radiator hose, sorry. It would be nice if you could do that. Since you have proven you can get water to flow thru your heater core, I wouldn't be so rash or wasteful of your resources, yet. I would focus on removing the air that seems to be trapped, most likely in your heater core, as it is high with small hoses relative to the rest of the cooling system. As with other bleeding operations, you may need to elevate the front of your car to force the bubbles to float out of the heater core. There is a very small bleeder hole in the tstat that can allow air out to the radiator, but it may take a long time. At the same time, you will need to top off the radiator as the coolant level drops, helping with the air removal and insuring air doesn't return to the heater core, etc. when you lower your car. If you need to or are impatient, you can disconnect the supply side heater hose at the thermostat (right side) to let the trapped air out, but you may only get coolant if you don't have much air to bleed. Worse come to worst, the core may need to be chemically descaled either by you, a rad shop, or replaced. Look inside the radiator, hoses and wherever else to see if there is a lot or some white to tan buildup, an indication of a calcium or another buildup that may be plugging the lower part of your heater core. One last test on your heater core is to feel how hot the two hoses to it are. The right one should be the hottest and the left one should not be nearly as hot. If one or both are much cooler than the bypass hose then something is blocking things or maybe your pump is no longer able to provide adequate flow and pressure, as some models have experienced an errosion of their pump blades. For some reason, I thought running your car without the tstat would be helpful in diagnosing and fixing your problem, but now I can't convince myself why. Have you looked to see if there is a blockage where the right heater hose connects next to the tstat? With that hose off and the fluid low enough, blow into it to see if you have blockage all the way thru the water pump, avoiding having to pull the line at the pump, not fun. Also, a properly filled and pressurized system will have a firm, fluid filled upper radiator hose. If it is empty or has a squishy fluid sound and feel, then you have air in your system. I don't remember if you have a new one, but a bad radiator cap can give you problems. Good luck. Hope this helps.

[Will Help]

I know Ford was having a lot of problems with water pump failures on 3.0 V6. Could be the same problem exists with 3.8. Took several years for problems to develop.

The problem involved the steel used in manufacturing the impellors. They were of cheap material and would start to deteriorate. I have an example that I kept. This one got so bad that it overheated and blew the head gaskets.

The pump impellor blades had corrode completely off the pump and the only thing left was a flat disk of steel. You cannot see this problem coming. I would check the pump ( needs replaceing anyway at 14 years old.).