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Car will not get up to operating temperature

  • Thread starter Thread starter tuhockey11
  • Start date Start date Dec 6, 2007
T

tuhockey11

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#1
  • Dec 6, 2007
  • #1
Only had the car for about a month. I figured the stock gauge was off when I got it as it never read above the L in NORMAL. Replaced the 180 stat with a 195 and gauge is the same, car never warms up. This is killing my gas mileage and also not getting me any good heat inside the car. Warm, but not hot. The rad hose never gets hot either. Gets warm, but not hot. Ive never had a problem getting a car to run warmer before, usually fighting the other way. What else can cause a car to run cool besides the thermostat? Running stock cooling system and fan btw
 

corvetteguy

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Jun 30, 2007
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#2
  • Dec 7, 2007
  • #2
Even new T stats can be deffective.

You might try an independent temperature
reading to verify.

When you start the car dead cold, watch the temp
gauge.
It shoud rise in 10 min or so straight past
normal into the danger area. Then
fall back to normal. That is the sign of
an operating T stat

 

ninety15.0

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  • Dec 7, 2007
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Have you verified the ACTUAL temperature with a known good gauge? I use an autometer pro-comp electrical water temp gauge and its deadly accurate! It will even show a minute change in temp when i climb a steep hill for an extended period of time...where as the stocker never really moved.

Get a real gauge on there and let us know as i suspect the heat and the temperature may be unrelated and could be a heater core problem.
 

wythors

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#4
  • Dec 7, 2007
  • #4
corvetteguy said:
When you start the car dead cold, watch the temp
gauge.
It shoud rise in 10 min or so straight past
normal into the danger area.
Then
fall back to normal. That is the sign of
an operating T stat
Click to expand...


Maybe on a Corvette, but I've never seen any other car that does that.

To the original poster:

Are you sure that you installed the t-stat correctly? What you're describing is a classic "thermostat stuck open" scenario.
 
T

tuhockey11

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#5
  • Dec 7, 2007
  • #5
it is acting exaclty like a stuck thermostat. Which way should it be installed? I just installed it the way it came out, maybe the previous owner had it wrong all along. The way it is now, the large spring is facing the housing (front of motor). Thinking to my other vehicles, this is incorrect. Could someone tell me for sure which way it goes? Also, the tmep gauge should not spike then come down, that is not normal in any car, GM, Ford, etc. The temp in my situation and the heat are directly related becuase the engine itself is not heating up, heater core is fine. Thanks for the suggestions guys
 

SuperStang83

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#6
  • Dec 7, 2007
  • #6
You might want to reinstall the thermostat to make sure it isn't in backwards.
 

wythors

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#7
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Yep, it's in backwards. The spring side goes into the intake manifold and the pointy end goes out towards the hose.

Edit:

Like this:



Gotta love Google image search.
 
J

Jmunk

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Sep 30, 2007
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Dec 7, 2007
#8
  • Dec 7, 2007
  • #8
My car only gets to the "L" on normal and puts out decent heat. Like others said the stock guages aren't the most accurate gauges.
 

BlownFiveLiter

have car, will race....wait, it doesn't run
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#9
  • Dec 7, 2007
  • #9
Make sure your coolant level is correct as well. Air pockets will most certainly throw off the gauge because it'll be reading air temperature versus coolant temperature. I am voting for thermostat stuck open though.
 

corvetteguy

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#10
  • Dec 8, 2007
  • #10
wythors said:
Maybe on a Corvette, but I've never seen any other car that does that.

To the original poster:

Are you sure that you installed the t-stat correctly? What you're describing is a classic "thermostat stuck open" scenario.
Click to expand...

Believe me, every car I have ever
owned requires heat to open the
T stat. They always pass the normal range to provide
that heat. It is just that most people do no focus their
attention on the dash when they first start out
on a ride to work.
Try it sometimes.
My 89 GT would scare me when the gauge was full scale
for a few seconds.

I suppose that you can design a T stat that would open a little
for the first time before the normal range. But most
american car parts just make them cheap
 

wythors

Get off my lawn!!!
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#11
  • Dec 8, 2007
  • #11
corvetteguy said:
Believe me, every car I have ever
owned requires heat to open the
T stat. They always pass the normal range to provide
that heat. It is just that most people do no focus their
attention on the dash when they first start out
on a ride to work.
Try it sometimes.
My 89 GT would scare me when the gauge was full scale
for a few seconds.

I suppose that you can design a T stat that would open a little
for the first time before the normal range. But most
american car parts just make them cheap
Click to expand...

Bold Italics Corvetteguy, every car you have ever owned apparently has malfunctioned. A t-stat has a temperature rating at which it opens, 180 or 190 for example. When the coolant in the block reaches that temperature, the tstat opens. On every car I have ever owned, seen or worked on in 20+ years in the car business, that temp is just about mid-point on a factory gauge or a little below. The "danger area", as you so eloquently put it, starts at 220* to 240*, depending upon the car. What really happens is that when the car warms up to the temp of the tstat, the tstat opens to allow coolant to flow through the radiator, then closes again when the radiator cools the coolant back below the rating and the engine stays within 10* +/- of that point unless you put some major strain on it. If your car spikes like that, you might want to take it to someone that knows what they're doing and have them put in one of those mysterious thermostats that open a little at a time, which is all of them by the way.


 

Mustang5L5

That is…until I whipped out my Bissell
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Dec 8, 2007
#12
  • Dec 8, 2007
  • #12
corvetteguy said:

When you start the car dead cold, watch the temp
gauge.
It shoud rise in 10 min or so straight past
normal into the danger area. Then
fall back to normal. That is the sign of
an operating T stat

Click to expand...


I've never seen any car i've driven do that
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Dec 8, 2007
#13
  • Dec 8, 2007
  • #13
What CG is describing could be fitting if he starts his Corvette and lets it idle in the driveway. The factory E-fan setting is probably quite high, so the gauge gets a ways up (even with the stat open) before the fan finally comes on and brings the temps down to mid-gauge.

That's the only plausable scenerio I could figure out. Otherwise, as Wythors and everyone said, the gauge should not spike as long as the stat opens and there is some airflow across the coil.
 
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