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Is my thermostat stuck open

  • Thread starter Thread starter SLY GT
  • Start date Start date Dec 19, 2005
S

SLY GT

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Oct 5, 2005
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Dec 19, 2005
#1
  • Dec 19, 2005
  • #1
Stock 02/Gt N.J.December weather and the guage does not move for a good ten minutes and the car does not fully warm up for about 10 miles or twenty minutes. Could this be normal? How long does it take for your car to warm up?
 

xseler8

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May 4, 2004
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Montgomery County,Pa.
Dec 19, 2005
#2
  • Dec 19, 2005
  • #2
SLY GT said:
Stock 02/Gt N.J.December weather and the guage does not move for a good ten minutes and the car does not fully warm up for about 10 miles or twenty minutes. Could this be normal? How long does it take for your car to warm up?
Click to expand...
Did you buy your car new or pre-owned.Are you the original owner. It could be the thermostat is crapping out. If pre-owned the last owner may have installed a cooler thermostat. Anyway,changing the thermostat is always a good move.Also,how is the anti-freeze? Check it. Does it have to be replaced.I think a hydrometer is used to check the protection level.
 

sgarlic

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Apr 21, 2001
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Dec 19, 2005
#3
  • Dec 19, 2005
  • #3
Normal. It takes my '04 ~10 minutes to warm up even in summer here in AZ.
 

DropTopPony

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Dec 19, 2005
#4
  • Dec 19, 2005
  • #4
Just change the T-stat...its easy and cheap. Just changed one myself. Also had the coolant flushed and filled. Actually made a difference in the heat.
 

DogVomit

Member
Jun 9, 2005
192
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Tampa, FL
Dec 21, 2005
#5
  • Dec 21, 2005
  • #5
FLORIDA - The temps are a cold 55 in the morning. It will stil take my stang a good 7-10 minutes driving "without S/C boost" before we get to a good operating temp. After I hit the first bar, there's plenty of heat coming from the motor, via the vents, then I know the thermostat has opened and the motor is warmed.

Still, it might take another 10 more minutes = 17-20 minutes before we get to normal operating temp.

This is based on only a 55 degree start.
 
D

Disturbed One

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Jun 26, 2005
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Dec 21, 2005
#6
  • Dec 21, 2005
  • #6
More often then not what I've seen come though at work is a customers cars radiator cap is not holding proper pressure. On my beater car for the winter, 89 chrysler new yorker, the cap is suppose to hold 16lbs and was only holding 8lbs. That's why my car did not warm up with a $hit. I'm not sure if our caps are self-venting, haven't looked, but I'd start with a cap and if you have the time a thermostat wouldn't hurt either.
 

menasci

Member
Aug 17, 2003
640
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Chandler, AZ
Dec 22, 2005
#7
  • Dec 22, 2005
  • #7
change the t-stat.
Might not be closing.
 

DropTopPony

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Dec 22, 2005
#8
  • Dec 22, 2005
  • #8
DogVomit said:
FLORIDA - The temps are a cold 55 in the morning. It will stil take my stang a good 7-10 minutes driving "without S/C boost" before we get to a good operating temp. After I hit the first bar, there's plenty of heat coming from the motor, via the vents, then I know the thermostat has opened and the motor is warmed.

Still, it might take another 10 more minutes = 17-20 minutes before we get to normal operating temp.

This is based on only a 55 degree start.
Click to expand...
AWWWWW It was 55 this morning I feel your Pain
 

sgarlic

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Apr 21, 2001
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#9
  • Dec 22, 2005
  • #9
You guys do realize he said 10 minutes right? In NJ December weather. That's below freezing. If your Mustang heats up faster than that in below freezing temps, make a video and post it here. I call BS on you ALL. Shame on you for recommending he start replacing parts.
 

DropTopPony

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#10
  • Dec 22, 2005
  • #10
sgarlic said:
You guys do realize he said 10 minutes right? If your Mustang heats up faster than that in cold weather, make a video and post it here. I call BS on you ALL.
Click to expand...
It takes more then 10 mins in the cold. I'll run my car for 1 cycle(15mins) with the remote start then still have a good 5 mins of driving until i have full heat.
 

Nater

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Sep 5, 2003
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Maplewood, MN
Dec 22, 2005
#11
  • Dec 22, 2005
  • #11
I was wondering the same thing too. I just had the coolant flushed and replaced and it doesn't warm up that fast. My boss' Chevy pickups warm up within a couple minutes. For my car it takes about 5 or so minutes of highway use before the gauge moves into the Normal range.
 

Jinx

I like cats, cats like me. Cats and I fully agree.
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Oct 2, 2003
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Dec 22, 2005
#12
  • Dec 22, 2005
  • #12
Instead of replacing it, why not test it? Place it in a pot of water on the stove that is metered with a thermometer, heat it up, and see if it opens at the proper temp.
 

ToplessStang

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Mar 7, 2004
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Dec 22, 2005
#13
  • Dec 22, 2005
  • #13
Just leave it, it's normal.
 

DogVomit

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Jun 9, 2005
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Tampa, FL
Dec 22, 2005
#14
  • Dec 22, 2005
  • #14
They warm slow. Let it be.
 

Stangsgrl

Member
Mar 13, 2004
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Mesa, AZ
Dec 23, 2005
#15
  • Dec 23, 2005
  • #15
Going through what i did this morning (~21deg). i let it sit for 15 minutes...the needle finally moved after about 12-13 minutes. I finally had warm air after driving 5 minutes.

You're normal...never hurts to check the fluids anyway though.
 

Nater

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Dec 23, 2005
#16
  • Dec 23, 2005
  • #16
Cars these days warm up faster when they are under a load rather than idling. I start it, let it run for a few seconds to get the oil circulating then go. Warms up a whole lot faster for me.
 
S

SLY GT

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#17
  • Dec 23, 2005
  • #17
DogVomit said:
They warm slow. Let it be.
Click to expand...

We have a winner. I changed it and no change. It takes a long time to warm up.
 

sgarlic

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#18
  • Dec 23, 2005
  • #18
I said that in the 3rd post of the thread, and nobody listens to me. Feh.
 
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