Good day all! Bear with me not car tech savvy, but learning. I have reviewed other associated threads and moved in the direction that some of you have suggested. Live in upstate NY and would like to have fixed soon. Here's what I've got going on.

Car: 2000, 3.0(Flex), 166K

Symptoms: Heat/Defrost will blow for a minute or two lukewarm at best. Then cold. Shut it off for a few minutes and turn on again same thing.

Checked (2 mechanics): Temp guage shows half way, Gasket seals are good, Hoses feel hot in and out of heater core, little white box with servo under dash works with temp select, 1 mechanic checked vents in dash all appear clear and functioning, fan blows strong, coolant level good/clean

New (because needed): Radiator, Thremostat, Bypass Line/s

Could it somehow be the heater core? Also, could there be something wrong with the hot/cold select switch on the dash (short) and how to check?

Any help would be greatly appreciated.

Thanks,
Golferguy

 

You might want to try to back wash the heater core. disconnect the heater hoses going in at the fire wall. Get yourself a couple of pieces of hose that are about 6'. I took a old garden hose and cut a split in the end so I can slide them on the heater core ends- it a little tight fit. Then I connected a garden hose to one end. I actually left the male end on one of the old pieces of hose so I can connect a good garden hose to it. Flush it with water and then swap the hoses and do the same the other way. I put the end of the hose that is not attached to the garden hose in a bucket and watch all the trash run into the bucket, then swap hoses again and watch again. I normally have to swap hoses about 4 times I run, I run water through the core both way until I see no trash coming into the bucket. This process takes about 45min.

Also get a couple of wooden dowels to use as plugs so you can plug the heater hoses so you won't loose alot of fluid.

I normally have to do this about every year and a half. When your coolant turns brown and you start seeing rusty looking coolant in your reservoir its time to do this. Also time to change coolant.

I've listed below the ford steps.

CAUTION: The heater core must be back-flushed separately from the engine cooling system for proper backflush water flow direction through the heater core.

DESCRIPTION
All engine cooling system flushing and back-flushing procedures must include a separate backflushing of the heater core, after the flushing or back-flushing of the engine cooling system. This will prevent engine cooling system particles from clogging the heater core tubes and reducing (or eliminating) coolant flow through the heater core.

PROCEDURES


1.Disconnect the heater core outlet heater hose from the return fitting. Install a female garden hose-end fitting adapter in the end of the outlet heater hose and secure with a hose clamp.
2.Connect the garden hose end of the outlet heater hose to the end of a water supply garden hose.
3.Disconnect the heater core inlet heater hose from the intake manifold fitting. Allow to drain into a suitable container.
4.If a water valve is installed in the heater core inlet heater hose, make sure the water valve is OPEN (no vacuum).
5.Turn the water supply valve ON and OFF several times so that the surge action will help to dislodge larger stubborn particles from the heater core tubes. Allow full water pressure to flow for approximately five minutes.
6.If a water valve is installed in the heater core inlet heater hose, apply vacuum to the water valve vacuum motor. This ensures proper operation of the water valve and proper closure with no water leakage. Replace the water valve if required.
7.Remove the hose clamp and female garden hose-end adapter from the end of the outlet heater hose. Reconnect the outlet heater hose onto the water pump fitting and heater return fitting.
8.Connect the inlet heater hose onto the engine block fitting and intake manifold fitting.
9.Fill the cooling system using the specified coolant mixture.
10.Test the system for proper heater performance with the specified engine cooling system conditions.

 

forthvacav, Thanks for the info. Will attempt a flush and post the results.

Golferguy

 

Flushed the system thoroughly. We get heat. Not not what you'd expect but much better than before. However, appears that the coolant level is slightly lower after a week. No noticeable drips on the ground and temp guage remains normal. Two mechanics looked at it and did not find anything. Any thoughts?

Thanks for the help

Golferguy

 

Good day all! Heat works ok when above 45mph. If you drive around town blows cool to lukewarm air. Also, defroster is not pushing the best air even at highway speeds. Any ideas?

Thanks

 

I have to do this same core flushing at least twice in a winter season on my '97 3.0 Vulcan wagon (bought brand new). I've tried flushing the system with the special pH Iron Cleaner (TSB stuff), Prestone chemicals, all to no avail. The system continues to generate crud forever!

Another thing I've done is replace my original water pump (at about 165k miles) last year (?). When I pulled it out I noticed it LOOKED very much intact (some had described completely rusted off vanes), but when I held it up to the sky I saw very narrow rusted slits through every vane right at the point where each vane bends 90 degrees. I would guess that these holes, though small, would contribute to a lower fluid pressure through the system (and less heat).

Also, don't know if this is the case with YOUR Taurus, but with my '97, Ford KNEW that these cooling systems would contaminate and sludge up - potentially causing major problems if the coolant was unable to flow through the heater core. So what did they do? They issued a TSB to install an "H"-shaped coolant hose that has a branch which runs parallel to the heater core. This way, even if the core plugs up - there will still be flow around the system. Problem with this "Kludge" fix is that less coolant flows through the heater core all the time - which means you get less heat in the winter.

What's you engine temp look like? If your thermostat is malfunctioning and is staying open most of the time, your coolant is constantly being cooled through the radiator and may not be getting hot enough to yield good heat. I'm not sure how you determine if this is the case (other than looking at your temp gauge on the dash). My temp gauge is always at mid-scale. If yours is lower than that, it may be an indication of a stuck open thermostat. I'd also add that I think a bad thermostat is a very rare occurrence (although mechanics will change them at the drop of a hat). In fact, I've never had to change a thermostat in 25 years of driving across a handful of cars.