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Is this normal? Temp gauge gets low while on highway

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Old 02-24-09, 08:51 PM
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KingNasGS4
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Default Is this normal? Temp gauge gets low while on highway

Hey I went on a nice run, maybe 80 or so miles
and I set the car to 80 mph cruising. and the temp gauge got down to nearly C

is this normal?
I asked my mechanic and he said that isnt a problem. cars run better when they are cooler and more air is flowing through the engine.

he said it would only be a problem when the gauge gets closer to H

so... is this true? or does my car really have a problem like I suspected?
Old 02-24-09, 09:13 PM
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LiCelsior
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ur mech is right...think about it. when ur idling is there any air being rushed through the radiator?? thats why when idling, ur temp gauge goes midway. once on the highway it should drop a pretty good amount and with the cold air in NY it gets even cooler.
Old 02-25-09, 02:32 AM
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python
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my gauge never moves once it gets to operating temperature....yours shouldnt either, your car is designed to run at a certain temp
Old 02-25-09, 05:09 AM
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ucfjon
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Originally Posted by python
my gauge never moves once it gets to operating temperature....yours shouldnt either, your car is designed to run at a certain temp
it's freakin cold in NY.....so its a possibility.
Old 02-25-09, 05:13 AM
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LiCelsior
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Originally Posted by python
my gauge never moves once it gets to operating temperature....yours shouldnt either, your car is designed to run at a certain temp
thats cuz u guys got warm weather...we got 20degree weather over here.
Old 02-25-09, 06:29 AM
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trukn1
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Agreed with above,, with the extremely cold weather once your car gets to operating temp. if you get on the highway and run em a good clip, you temp gauge will drop some with more of the cold air rushing thru the engine. As your mechanic stated, if your temp gauge keeps going up towards the H mark then there could possible be a problem with overheating (blockage in cooling system, clog, faulty thermostat, etc)
Old 02-25-09, 08:39 AM
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Bali26
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Hi Kosi,

Your theremostat is stuck open, causing an open flow thru radiator at all times. This causes highway speeds to drop the temp of your engine.

New thermostat is about $20, easy fix. Plus your gas mileage will improve a lot.

cheers.

PS: and change your mechanic. Cars run better when hot. Hottest possible.
Old 02-25-09, 09:11 AM
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genetic
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Originally Posted by Bali26
Hi Kosi,

Your theremostat is stuck open, causing an open flow thru radiator at all times. This causes highway speeds to drop the temp of your engine.

New thermostat is about $20, easy fix. Plus your gas mileage will improve a lot.

cheers.

PS: and change your mechanic. Cars run better when hot. Hottest possible.
This was what i was going to say

my old car had the same problem, where the theremostat stuck open. But i mean i never did anything to it so it shouldn't be a problem, it just never really warms up. I'd replace it anyways if its only $20
Old 02-25-09, 12:55 PM
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trukn1
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If your car is doing this constantly, whether it is cold or hot outside then the thermostat is the culprit as suggested. If it only does this when it is cold, mine does the same thing but only in the cold weather, then you are fine. Keep an eye on it, especially on a nice warm day ABOVE 40 degrees, and see if the problem still exist. Mine drops to 1 line above the C mark on a very cold day, on a normal warm day it is, and stays, directly in the middle of the gauge. I am in MD, so I know the symptom that you are speaking of; is about 30 down here.
Old 02-25-09, 06:05 PM
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Rocan
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hot engines wear more, use up more oil, have less power.

if hot engines were better, wouldnt the air intake be right under the headers?

Keeping an engine cool is essential... if you think a hot engine is better, you need to SERIOUSLY think a little bit more before you modify your car one more time.

why would you think drag racers cool their engines by spraying nitrogen all over them?
Old 02-25-09, 09:52 PM
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PureDrifter
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tooo cold an engine yields a motor that doesnt function at it's peak performance.
Old 02-26-09, 11:02 AM
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19psi
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Originally Posted by Bali26
Hi Kosi,

Your theremostat is stuck open, causing an open flow thru radiator at all times. This causes highway speeds to drop the temp of your engine.

New thermostat is about $20, easy fix. Plus your gas mileage will improve a lot.

cheers.

PS: and change your mechanic. Cars run better when hot. Hottest possible.
x2 on everything.

Originally Posted by Rocan
hot engines wear more, use up more oil, have less power.

if hot engines were better, wouldnt the air intake be right under the headers?

Keeping an engine cool is essential... if you think a hot engine is better, you need to SERIOUSLY think a little bit more before you modify your car one more time.

why would you think drag racers cool their engines by spraying nitrogen all over them?
an engine must be kept in it's proper operatin gtemperature for maximum performance. that's usually on the hot side. that's why we have thermostats, to regulate engine temp. otherwise we have either super hot or cold engine temps, neither of which is good.
intake air must be cold, but actual engine temperature must be hot for proper and efficient combustion. otherwise you end up wtih bad fuel mileage, carbon deposits, less than maximum power, poor emissions, etc.
pick up a performance engine book next time you're at the bookstore, you'll find in greater detail why engines must be hot.
Old 02-26-09, 07:42 PM
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Rocan
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Originally Posted by 19psi
an engine must be kept in it's proper operatin gtemperature for maximum performance. that's usually on the hot side. that's why we have thermostats, to regulate engine temp. otherwise we have either super hot or cold engine temps, neither of which is good.
intake air must be cold, but actual engine temperature must be hot for proper and efficient combustion. otherwise you end up wtih bad fuel mileage, carbon deposits, less than maximum power, poor emissions, etc.
pick up a performance engine book next time you're at the bookstore, you'll find in greater detail why engines must be hot.

my mistake, i misread his post thinking that he was saying an engine must be as hot as possible.

i have 4 books on 4 stroke theory, 3 on 2 stroke theory, and 1 on diesel engines...

dont worry, i understand how an engine works fairly well
Old 02-27-09, 06:19 AM
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19psi
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ha ok it's cool.... i wasn't trying to be an *** or anything.
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