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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

think my thermostat is screwed

  • Thread starter Thread starter grendel
  • Start date Start date May 3, 2005

grendel

New Member
Apr 23, 2004
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May 3, 2005
#1
  • May 3, 2005
  • #1
my car starts to overheat when driving through town while idleing and light to light driving. on the highway it is fine, the temp gauge doesnt even move. could the reason for this be that my thermostat has gone bad? how is there a way to check it?
 

road rage

New Member
Dec 14, 2003
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R.I.
May 3, 2005
#2
  • May 3, 2005
  • #2
yup sounds like thermostat, but also listen to see if the fan is kicking on while in traffic.
 
K

Kilgore Trout

Fried or Broiled ?
10 Year Member
Mar 30, 2005
4,749
95
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May 3, 2005
#3
  • May 3, 2005
  • #3
You can test the thermostat by taking it out and boiling it in water while you monitor the temperature of the water with a thermometer. But screw that, just replace it! www.fordracingparts.com has cool ones...
 

COramprat

...I can take it. I think.
20+ Year Stangneter
Mar 2, 2003
8,474
1,463
223
Sea of Tranquility
May 3, 2005
#4
  • May 3, 2005
  • #4
They aren't expensive. Just swap it out...maybe with a cooler than stock if you prefer.
 

grendel

New Member
Apr 23, 2004
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May 3, 2005
#5
  • May 3, 2005
  • #5
my car is to damn loud to hear the fan, haha
 
J

Jakes

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May 8, 2004
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May 4, 2005
#6
  • May 4, 2005
  • #6
Like someone else said, make sure your fan is cycling properly. Sounds to me more like the fan not coming on. Good air flow on the highway but none when you're driving in town (no fan). If the thermo were stuck closed or part way closed you'd run hot on the highway too.
 
D

Darkhorse845

Banned
Nov 17, 2004
101
0
0
Las Vegas,Nevada
May 4, 2005
#7
  • May 4, 2005
  • #7
They are cheap get a 180 degree Stant
Thermostat.
 

white99gt

Founding Member
Aug 8, 2000
4,649
1
0
stockbridge,Ga(near atlanta)
May 4, 2005
#8
  • May 4, 2005
  • #8
If it doesnt overheat on the highway its NOT the thermostat.The coolant fan is NOT coming on ,this is what keeps it from overheating around town.

If the tstat was bad the issue would be at highway speeds and around town.
 

xseler8

Member
May 4, 2004
619
0
17
Montgomery County,Pa.
May 4, 2005
#9
  • May 4, 2005
  • #9
white99gt said:
If it doesnt overheat on the highway its NOT the thermostat.The coolant fan is NOT coming on ,this is what keeps it from overheating around town.

If the tstat was bad the issue would be at highway speeds and around town.
Click to expand...
I agree with these replies.
 

grendel

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Apr 23, 2004
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May 4, 2005
#10
  • May 4, 2005
  • #10
but at highway speeds wouldnt there be enough air going through the radiator without the fan to keep it cool?
 
K

Kilgore Trout

Fried or Broiled ?
10 Year Member
Mar 30, 2005
4,749
95
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May 4, 2005
#11
  • May 4, 2005
  • #11
Yes, that is what they are saying. Since it does not overheat at highway speeds it is not the thermostat. It is most likely the cooling fan. Do you have underdrive pulleys? Do you use water wetter?

Let it heat up and then check the fan to see if it is spinning.
 

grendel

New Member
Apr 23, 2004
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May 4, 2005
#12
  • May 4, 2005
  • #12
ok, next time i drive my car around for a while i will check it. i dont have pulleys or use water wetter
 

white99gt

Founding Member
Aug 8, 2000
4,649
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0
stockbridge,Ga(near atlanta)
May 4, 2005
#13
  • May 4, 2005
  • #13
grendel said:
ok, next time i drive my car around for a while i will check it. i dont have pulleys or use water wetter
Click to expand...

If its over heating ,I would not keep driving it till its fixed.

If its gonna over heat it will do it in your driveway if the coolant fan isnt working.

If a thermostat was bad,I dont care if you were going 150mph its not gonna cool off.
 

Hungry4Horses

New Member
Aug 26, 2004
42
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0
Fremont, CA
May 4, 2005
#14
  • May 4, 2005
  • #14
You can see if you thermostat opens easily. Idle your car and wait for the gauge to start moving up. If the thermostat is working it will open and water moves through the radiator hose. If you feel the radiator hose it feels hot when water is flowing through it. The Radiator hose doesn't get scorching hot just hot enough to not be able hang on to the hose. You can probably feel the water flowing through, I can with mine. Good luck man.
 

CanadaStang

New Member
Sep 7, 2003
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Mb
May 4, 2005
#15
  • May 4, 2005
  • #15
grendel said:
my car starts to overheat when driving through town while idleing and light to light driving. on the highway it is fine, the temp gauge doesnt even move. could the reason for this be that my thermostat has gone bad? how is there a way to check it?
Click to expand...

When you say " the temp gauge dosen't even move" do you mean it doesn't come off of cold? Or do you mean it doesn't move past normal?
 
S

SVTLink

New Member
Mar 30, 2005
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Garland, Tx
May 5, 2005
#16
  • May 5, 2005
  • #16
If it is the fan, how could you correct the problem? I have the same problem, my fan doesn't come on the low speed, but works on the high temp. I was thinking it was the temp coolant sensor or the actual fan? Can anyone shed any light on this?

Mr. noob
 
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