Engine running hot

Tiny
JOHNNY G.JR
  • MECHANIC
  • 320 POSTS
Are the cooling fans behind radiator coming on
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Saturday, December 2nd, 2017 AT 2:54 PM (Merged)
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 48,363 POSTS
Hey Michelle,

It sounds like you have a blown head gasket, here is a test you can use to help determine of that is the problem or not.

https://www.2carpros.com/articles/head-gasket-blown-test

and

https://www.2carpros.com/articles/engine-overheating-or-running-hot

Best, Ken
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Saturday, December 2nd, 2017 AT 2:54 PM (Merged)
Tiny
CATO
  • MEMBER
  • 1 POST
  • 2000 CADILLAC DEVILLE
  • V8
  • 2WD
  • AUTOMATIC
  • 186,000 MILES
Engine Cooling problem
2000 Cadillac Deville V8 Two Wheel Drive Automatic 186000 miles

I have a 2000 Cadillac Deville, It will run hot if I drive around 70 miles per hour for a period of time or if I run the air conditioner, I will have to turn the air off and turn the heat on until the engine get back to its normal temp. I have replaced the water pump and the Thermostat and there are no leaks, what could cause this?
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Saturday, December 2nd, 2017 AT 2:54 PM (Merged)
Tiny
BMRFIXIT
  • MECHANIC
  • 19,053 POSTS
Check coolant fan operation
fan should come on and not allow the engine to over heat
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Saturday, December 2nd, 2017 AT 2:54 PM (Merged)
Tiny
MARK BROCK
  • MEMBER
  • 1 POST
  • 2000 CADILLAC DEVILLE
  • V8
  • FWD
  • AUTOMATIC
  • 139,000 MILES
It wants to run hot all the time I replace the water pump thermostat fan relays.
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Saturday, December 2nd, 2017 AT 2:54 PM (Merged)
Tiny
HMAC300
  • MECHANIC
  • 48,601 POSTS
Have this checked for a blown head gasket. It may be that I am assuming you already did thermostat etc. Then check when hot and engine off, fans disconnected for cold spots on radiator it should be about same tem p all ove if not the rad is bad. One other thing if coolant was run at higher than a 50/50 ratio it eats the aluminum up in bottom of block where head bolts go in and has to be torn apart and heli coils put in block. So it would be same thing as a blown head gasket but more severe
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Saturday, December 2nd, 2017 AT 2:54 PM (Merged)
Tiny
N_TREEG
  • MEMBER
  • 1 POST
  • CADILLAC DEVILLE
1996 Cad Deville. 75K We noticed last week when the outside temp reached 100+, the air conditioner was only 'cool', then we noticed that the car was running at 216-223. We had freon added and checked radiator coolant. All looked good. The outside temp has now lowered to 75, and the car is still running at 190-208 (generally the higher). We don't know what it normally ran at, I guess because it doesn't get that hot around here to need A/C often, so I didn't pay attention to the engine temp. With all the 'dummy' lights this thing has, I was sure it would tell me if anything was wrong. We haven't gotten any messages. (The check emissions light came on a month or so ago, but went off) A friend said perhaps the water pump was going out? We wondered about the thermostat. It has never 'overheated' beyond us noticing on the dash that the temp was high, and that the air wasn't cold. I ran with the heat, with vent only, every option to try to lower the engine temp but nothing worked (maybe newer cars don't cool down that way like my old ones did?) We are a single income family of 5 1/2 and this is our main car. Because we don't have a 'trusted mechanic' ourselves, and we aren't 'car smart' we really hope to have a direction to look before taking it in. Every penny helps in this family! Thanks for any help you can provide.
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Saturday, December 2nd, 2017 AT 2:54 PM (Merged)
Tiny
2CARPRO JACK
  • MECHANIC
  • 11,533 POSTS
Internal combustion engines are heat generators all by themselves, when ambient temp rises, so will the underhood temps. The a/c problem. When it is running are both cooling fans running?If not then have them checked out.
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Saturday, December 2nd, 2017 AT 2:54 PM (Merged)
Tiny
RAY BEATTY
  • MEMBER
  • 1 POST
  • 1996 CADILLAC DEVILLE
Engine Cooling problem
1996 Cadillac Deville V8 Front Wheel Drive Automatic

HOW CAN I FIX THE PROBLEM OF IT RUNNING HOT
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Saturday, December 2nd, 2017 AT 2:54 PM (Merged)
Tiny
FACTORYJACK
  • MECHANIC
  • 4,159 POSTS
It all depends on the symptoms that lead to it running hot. It could be a stuck closed thermostat, in which you will have little heat, and a cool upper radiator hose when it says overheat. You could also have an internal leak, causing superheated combustion gases to enter the cooling system. If you have heat and the upper hose is hot, the first dollars I would spend is on a block test for combustion gases in the radiator. Internal leaks are common cause of overheat on Northstars.
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Saturday, December 2nd, 2017 AT 2:54 PM (Merged)
Tiny
PROFITSON
  • MEMBER
  • 12 POSTS
  • 2000 CADILLAC DEVILLE
  • 167,000 MILES
I got a 2000 cadillac and I put a ratiator waterpump and throma and bleed the lines still run hot
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Saturday, December 2nd, 2017 AT 2:54 PM (Merged)
Tiny
DRCRANKNWRENCH
  • MECHANIC
  • 3,380 POSTS
There could be a crack in the block or you have a bad head gasket.
You can get a coolant system pressure test done to see if it is holding pressure up to specification. Pressure is necassary for the cooling sytem to work.
Also, have you confirmed that the cooling fan(s) are working. Make sure they come on when the engine reaches operating temperature. This should be around 200 degrees farenheit. You can get an infra-red temperture gauge for under $20 at most auto parts stores. Point it at the thermostat housing and compare it to the dash gauge and see when the fan comes on. You can also check fan operation by turning on the A/C and the condenser fan should come on rather quickly if not immediately.
If the fan does not come on, there is an electronic PCM control that acts as the realy that could be bad or the temperautre sensor could be bad.
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Saturday, December 2nd, 2017 AT 2:54 PM (Merged)
Tiny
4SAXMAN
  • MEMBER
  • 1 POST
  • 1994 CADILLAC DEVILLE
  • V8
  • FWD
  • AUTOMATIC
  • 205,000 MILES
Where is the thermostat in a 1994 Cadillac Seville?
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Saturday, December 2nd, 2017 AT 2:54 PM (Merged)
Tiny
FACTORYJACK
  • MECHANIC
  • 4,159 POSTS
4.6 Northstar is at the engine side of the lower radiator hose. It is installed in the cover that is over the water pump access.
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Saturday, December 2nd, 2017 AT 2:54 PM (Merged)
Tiny
KZAP
  • MEMBER
  • 3 POSTS
  • 1997 CADILLAC DEVILLE
  • V8
  • FWD
  • AUTOMATIC
  • 56,000 MILES
How do I fix this 97 caddy.
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Saturday, December 2nd, 2017 AT 2:55 PM (Merged)
Tiny
FACTORYJACK
  • MECHANIC
  • 4,159 POSTS
Not really enough specifics to form an educated guess on. You could have issues of secondary ignition, fuel pressure, primary items like crank sensors. Is there a check engine light associated with said concerns?
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Saturday, December 2nd, 2017 AT 2:55 PM (Merged)
Tiny
2CP-ARCHIVES
  • MEMBER
  • 4,540 POSTS
  • 2000 CADILLAC DEVILLE
  • 113,000 MILES
My car constantly runs hot and frequently needs coolant added. I can only travel about 10 miles before it runs hot and I need to stop to let it cool off. Where is the coolant going and what repairs are necessary to avoid this problem?
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Saturday, December 2nd, 2017 AT 2:55 PM (Merged)
Tiny
CADIEMAN
  • MECHANIC
  • 3,544 POSTS
Are the cooling fans operating? Does the coolant bubble in the overflow Jug?Start here.
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Saturday, December 2nd, 2017 AT 2:55 PM (Merged)
Tiny
KIRAM CROWDER
  • MEMBER
  • 1 POST
  • 1997 CADILLAC DEVILLE
  • 4.6L
  • V8
  • FWD
  • AUTOMATIC
  • 150,643 MILES
Why does my car runs hot, continuously?
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Saturday, December 2nd, 2017 AT 2:55 PM (Merged)
Tiny
CARADIODOC
  • MECHANIC
  • 33,916 POSTS
There's dozens of possibilities. You need to provide some details or observations. At what speeds? How much too hot? What affects it? Is the air from the heater too hot or too cold? What are the symptoms?
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Saturday, December 2nd, 2017 AT 2:55 PM (Merged)

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