Mechanics

HEATER BLOWS HOT FOR 1 MINUTE THEN COLD

2001 Ford Taurus

Heater problem
2001 Ford Taurus 6 cyl Front Wheel Drive Automatic 118k miles

Ok. My car blows hot air for just a minute or so then goes cold on me. If I turn the heater off for a minute then back on. I have hot air again but only for a mintue or so. I have changed the thermostat and with my luck I have cracked the housing. LOL. So I have a new thermostat and housing. I have went in and taken the heater hoses connected them to a water hose and clamped the bypass hose off next to the fire wall and got good clean water flowing through. I did that in reverse as well by changing sides. I have turned the car on and just turned the heater dial from cold to hot on and off to see if the blend door is working. I do hear it running. WHAT IS MY PROBLEM. How do I double check the blend door to see if it is just stuck or stripped or whatever before I spend 8 hours of my day changing a heater core that may not need replaced? Please help me before my wife takes my car and makes me drive hers. Its funny but its that or I fix it. You know the wife will win the battle in the end. So someone please help me. If possible please give detail intsructions or pics. I am not totally a beginner but need help and can follow directions very well if detailed.

Thank you for your time and help.
Avatar
Slydawg1213
October 9, 2009.




Not the wife threat!
LOL.

So just to understand, did you flush the heater core?

Yes I am assuming so. I took the heater hose from right behind the thermosat on drive side by firewall. Put a fitting on it hooked it up to a garden hose. Took the heater hose on passenger side coming from the firewall and hooked a hose up to it as well but ran it along side of the car. Clamped the bypass hose with a pair of vise crips and a towel over the hose then pinching together. Turned on water came out clean. Hooked garden hose up to passenger side hose and did it in reverse and water came out fine. No dirt or chunks of anything came out. No smell on inside of car and no leak found so heater core seems to be good? So did I flush the core and is the core still good sense it did not burst from the pressure from the hose. What is my next step.

Yes I got threatened by the wife. I laughed but she was serious.

Tiny
Slydawg1213
Oct 9, 2009.
I want you to bring the engine to operating temperature. Feel both the inlet and outlet hose for the heater core. They both should be hot. Then hold the rpm 1500-2000. Do you get better heat? Higher rpm means higher flow rate and may heat the portion of the core that is not plugged.

There are two common problems with these cars.

First the heater cores are apt to plug up. Having clean water come out when backflushing is a surprise, but flow may still not be what it should be. That is a larger volume of coolant is not going through as it should.


http://www.2carpros.com/forum/automotive_pictures/30961_P2220004_1.jpg

This was a shot of a plugged core after it dried.


http://www.2carpros.com/forum/automotive_pictures/30961_P4250002_1.jpg


Sludge build up in a radiator.

One option to try is to warm up engine then disconnect heater hoses,turned them up and filled core with radiator flush (or muriatic acid-about a 10% solution), left sit a couple hours and then flush again, pull bypass hose and blocked off with a couple rubber caps or however you choose. If both hoses were hot as mentioned in the beginning, then I would expect the heater core should be in an acceptable condition to provide heat.

The second common problem is worn impellers on the waterpump. They erode enough that the coolant circulate not quite well enough to provide heat.
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I took the vehicle in to get a power flush. The radiator cap was no good. There was no pressure on the system. I was also told that I had an air pocket in the heater core. So after replacing the radiator cap and flushing the air pocket out (lol) the system works fine.

Tiny
Slydawg1213
Oct 11, 2009.
" See Honey.I told you I had it under control! LMAO!
Congrats!


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