Question about 1999 Cadillac DeVille

1 Answer

1999 cadillac false overheat

Engine temp rises quickly (intermittent) to overheat. Yet, when you open the hood it is not hot under the hood and fans are not running. Shut down for 5 seconds and restart and you get engine temp at about 217 and will cool to 199-205 depending on outside temp. You can keep driving until this happens again.

Posted by Anonymous on

Ad

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Superstar:

    An expert that got 20 achievements.

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

  • Cadillac Master
  • 3,926 Answers

Bad temp sensor or wiring harness issue.

Posted on Dec 31, 2017

Ad

5 Suggested Answers

6ya6ya

6ya staff

  • 2 Answers

SOURCE:

Hi there,
Save hours of searching online or wasting money on unnecessary repairs by talking to a 6YA Expert who can help you resolve this issue over the phone in a minute or two.

Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.

Here's a link to this great service

Good luck!

Posted on Jan 02, 2017

Ad

ziad ahmad

  • 117 Answers

SOURCE: Cooling fan runs constantly. Car overheats.

check engine temp sensor if ok check fan relay

Posted on Jul 07, 2009

Kravcar

Mark Carrington

  • 192 Answers

SOURCE: 1998 Cadillac Deville overheating

The most common overheating problem with the Northstar engine is a blocked purge line. It's job is to purge air out of the cooling system.
There is a small diameter hose coming from near the top of the coolant tank,this is the purge line.
With the engine idling,pull the purge line from the tank,if there is no coolant flow from this small hose,it is blocked and this will cause overheating.If the hose is clear, check for blockage at the nipple on the tank.Or trace the hose back until you find the blockage.The hose goes in to the engine to a crossover and comes out the other side to near the thermostat housing,the blockage may be there.

Posted on Mar 28, 2010

Kravcar

Mark Carrington

  • 192 Answers

SOURCE: 98 deville 32 valve North Star OVERHEATS after 33

The most common overheating problem with the Northstar engine is a blocked purge line(small hose).The purge line is designed to purge air out of the cooling system.
There is a small diameter hose coming from near the top of the coolant tank (not the cap) ,this is the purge line.
With the engine idling,pull the purge line from the tank,if there is no coolant flow from this small hose,it is blocked and this will cause overheating.
If the hose is clear, check for blockage at the nipple on the tank.Or trace the hose back until you find the blockage.
The hose goes in to the engine to a crossover and comes out the other side close to the thermostat housing,the blockage may be there.
Also note that the cooling fans don't come on until the coolant temperature hits around 225 degrees.
During normal highway driving the fans will very rarely come on(if at all) due to constant air flow through the radiator.They will only usually come on in heavy traffic conditions on a hot day.
But......if you have the Air Con switched on, the fans will run all of the time.

Posted on Jul 17, 2010

Frank Meert

  • 610 Answers

SOURCE: 99 cadillac deville engine overheating an loosing

Check to see if you have flow through the entire radiator.If part of the radiator core is cool to the touch when the engine is at operating temp, this indicates restricted radiator flow. If the entire radiator core is not allowing water to flow through, cooling will not be at all efficient. Also a good idea would be to purchase a block tester. available at napa and other reputable parts houses for around thirty dollars. You remove a small amount of coolant, and put the tool in the radiator, or pressure tank opening. If there are any combustable gasses present, i'e' exhaust, this would indicate a head gasket breech, (or maybe worse) and would indicate that it's time to stop looking for a simple problems, and get proffessional help. Good luck to you!

Posted on May 12, 2011

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

2 Answers

Why don't the fans turn on,on mitsubishi lancer


Could be an electric fan that only turns on when engine is hot and needs cooling

Sep 15, 2014 | Cars & Trucks

1 Answer

2000 BMW 528i running hot


is the cooling fan cutting in ? run the engine whilst stationary with the hood up , give it a little gas 2000revs and wait for the temp gauge to rise ,the cooling fan should be heard cutting in , and off again once cooled the engine temp down ,this may take 10-15 mins but you have to be sure the fan is cutting in or you may cook the engine

Jun 03, 2014 | 2000 BMW 528i

1 Answer

Car only overheats when a/c is turned on.? is there a coolant temp sensor or not?


Yes there is a sensor. It tells the PCM the engines temp and from there a number of things are going on.

Have the car running and turn the a/c on and look under the hood at the cooling fan(s). If the fan is not on immediatly wait for a minute as they may come on when the a/c pressure rises and not right when the a/c is turned on.

The a/c condensor gets very hot. That would make the air being drawn in hotter than normal. The engine temp may rise higher than normal as well. Is it really over heatting or just running a bit hotter.

Aug 31, 2011 | 2001 Lincoln LS

1 Answer

My 1999 mazda 626 6 cylinder overheats if traffic slows down for very long, stop for a train, etc. At other times the air coming out of the vents is very cold. I have added coolant several times.


Your radiator fan is probably failed. Pop open hood, watch temp rise, once past "normal " level teh fan should turn on. If not, you need to trouble shoot the rad fan. There should be heavy duty fuses and relays under the hood in an electrical distribution box. You should consult the owners manual or chart on the box lid. Of course the fan maybe bad itself. You can also try - turn on the AC, this will activate the 2nd (booster) fan, and should help prevent serious overheating but wont fix the underlying problem.
Good luck

Jul 13, 2011 | 1999 Mazda 626

1 Answer

2000 Oldsmobile Bravada. Engine is running hot, and I have intermittent heat. I've replaced the thermostate last week and now the problem is worse than before. Engine will get up to 260 check gauges light...


CHECK FOR LOW COOLANT.YOUR CLUTCH FAN COULD BE BAD IT CAUSING ENGINE TO OVERHEAT.WHEN ENGINE GET HOT THE SILICONE OIL IN FAN CLUTCH GET HOT CAUSE THERMOSTAT SPRING EXPAND CAUSE FAN CLUTCH TO LOCK IN TURN FAST WITH ENGINE TO COOL OFF ENGINE. IF FAN IS WOBBLY OR FREEWHEELING ITS BAD.

Dec 17, 2010 | 2000 Oldsmobile Bravada

2 Answers

Car is running hot (temp gauge rises above normal)


Try the overflow tank cap. The seal will go bad and not hold the psi causing the water to flow out this is something you will not always see which will cause the engine to overheat or temp gauge to rise. Also the thermostat could be sticking and cause the temp gauge to rise. Are the fans turning on when the temp gets high? If so then I would resort to the above first. If the fans are not coming on, the relay or fan/s could be the problem.

Jun 29, 2010 | 1996 Mercedes-Benz C-Class

1 Answer

Electric cooling fans will work.


The fans are actuated by coolant temp in the radiator. It is possible to have overheated coolant in the radiator, causing the steam, and your engine not overheating...the temp sensor for your engine is reflecting the engine temp, not the temp of the coolant in the radiator. You problem could be a bad temp sensor at the radiator...not allowing the fans to come on. Good Luck! I hope you find this to be very helpful!

Dec 14, 2009 | 2000 Dodge Caravan

1 Answer

Cooling fan runs constantly. Car overheats.


check engine temp sensor if ok check fan relay

Jul 07, 2009 | 1998 Cadillac Eldorado

1 Answer

Intermittent overheating 96 Subaru Legacy.


if it overheats while your in motion then u can eliminate your fans, as your problem. and do you mean 5-50 thousand miles? id chech your coolant for hc contamination. most likley a head gasket

Mar 15, 2009 | 1999 Subaru Legacy

1 Answer

92 eldorado coolant fans dont come on


the fans have relays that are located in the fuse box under the hood on the driver side. a quick check involves just switching the a/c clutch relay with the fan relay if they turn on when engine is hot the relay is bad. if not that means there is a bad connection or the temp probe is bad. make sure no loose or frayed wires are present. hope this helps. please rate this solution. thank you.

Aug 29, 2008 | 1999 Cadillac Eldorado

Not finding what you are looking for?
1999 Cadillac DeVille Logo

Related Topics:

162 people viewed this question

Ask a Question

Usually answered in minutes!

Top Cadillac Experts

Marvin
Marvin

Level 3 Expert

85216 Answers

Jonah Oneal

Level 3 Expert

14092 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22485 Answers

Are you a Cadillac Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...