: Check Coolant Level Message & temp. question



budgarrett
01-12-04, 04:05 PM
A little help please. I recently purchased a 1998 Deville dElegance. It was a one owner, low milage (32k miles) very well maintained vehicle. It has the digital dash so the "coolant temp." is displayed in actual degrees rather than a gage.
I had it about a week and was thrilled with its comfort and driving. Then one day the "check coolant level" message came on. I pulled over immediately, the engine seemed cool, I checked the level but it was hard to see. The engine normally runs at 197 almost all the time. However when I stop in traffic or pull a small hill, it may slowly climb up to 204-215 degrees. Then it will go right back down to 197 upon take off or normal driving.
I took it to the local dealer to have it checked. They pressure checked for leaks and couldn't find any. They said they added "a very small" amount of coolant but thought everything was normal.
It's pretty much done the same thing as far as the temperture goes (mostly 197 then up to 204-210 for short periods) The check coolant message has come on twice since then which was about 4 weeks ago, but then goes away and the coolant seems to be full.
This car is not my daily driver so I have only put about 500 miles on it since I purchased it. Also, there seems to be a slight smell of antifreeze in the enterior of the vehicle. It's so slight that I'm not even sure that's what it is but that's what it smell like to me.
I want to use this car on the highway for long trips but I'm a little afraid to until I have more confidence. I guess my main questions are.. 1. is the temp. range 197-214 normal(in cooler weather)....and 2. What about the "check coolant temp"message....and 3. How can I know for sure that what I'm smelling is actually antifreeze??
A little help from those more knowledgable will be greatly appreciated. This is my first "post" so be kind.

elwesso
01-12-04, 06:27 PM
Welcome to the forums, thanks for signing up :wave:

1. Yes, your temp is normal.... The northstar runs much hotter than most cars, than we are used to.... This is a common concern for most new owners, and is NOT something to be worried about.... Keep it below 240ish and your golden!!

2. My guess about the check coolant message is that you have air bubbles (possibly) and/or you have a slight leak.... There are many hoses right above the block, and it wont leak to the ground.... In fact, there are very FEW hoses that will make leaks obvious..... Its also possible the coolant level sensor is bad.....

3. I bet you have a slightly leaking heater core... its a common item and is easy to fix..... This could be where your leaking coolant is coming from.....

As long as you keep close eye on the REAL coolant level and the temp, i wouldnt worry too much.....

hemhem71
01-12-04, 09:59 PM
Well it still worries me cause now in the winter being about 20-50 degrees it goes all the way up to 223-235 just idling

mike98c
01-12-04, 10:31 PM
Well it still worries me cause now in the winter being about 20-50 degrees it goes all the way up to 223-235 just idlingYou can open the hood when the temp climbs at idle and make sure the low speed fan comes on. The fans won't come on at all until the temp. goes above 220 I believe. You can also turnon the Air to check the fans but the temp. outside has to be above forty or fortyfive degrees for the defrost or air to kick in. That said my car has always run warmer at idle during the winter because the fans don't kick in as frequently as they doin the summer. Also if you run the air in the summer the car will idle at a lower temp, because the high speed fan will run as long as the air is on.
Is 235 degrees to high? Thats the temp. my car will reach occassionally while idling in the winter temps. That's also (230-235) what I've seen other posters on forums report as normal temperatures.

BeelzeBob
01-12-04, 11:19 PM
Well it still worries me cause now in the winter being about 20-50 degrees it goes all the way up to 223-235 just idling
That temp is perfectly normal. The fans don't even kick on until 225.

Surprisingly you will often see hotter coolant temps idling in the winter than in the summer. This is normal. The cooling fans are controlled by coolant temp and by the AC load. The AC condensor needs constant airflow over it so the cooling fans will run virtually all the time the AC is on or the climate control is in Auto/defroster on. In the winter when the AC compressor is disabled (temps below 40 degrees or so...) the fans will not run due to the AC system. They operate solely on the coolant...and they do not come on until 225. In the summer with the AC load and the fans constantly running to keep the condensor cool they will also keep the coolant temp on the stat...not becuase the coolant needs to be that cool but because the fans running for the AC provide "latent" cooling for the rad also.

It is desireable for the engine to run above 212 or hotter, especially in the winter. In addition to better fuel economy, the hotter coolant temps warm up the oil in the engine and drive the moisture out of the oil. A great deal of moisture gets into the oil in the winter on cold starts. Water boils at 212...so...it is good to get the coolant above 212 to drive the moisture out of the oil so the PCV system can get it out of the crank case.

The cooling sytem in your car operates at a pressure of 15 PSI and with a 50/50 ethylene-glycol coolant mixture. This system will not boil until 265 F. Temperatures up to 240-245 are considered perfectly normal and acceptable. Just get used to it. The lower coolant temps of yesteryear are really not desireable.

BeelzeBob
01-12-04, 11:28 PM
A little help please. I recently purchased a 1998 Deville dElegance. It was a one owner, low milage (32k miles) very well maintained vehicle. It has the digital dash so the "coolant temp." is displayed in actual degrees rather than a gage.
I had it about a week and was thrilled with its comfort and driving. Then one day the "check coolant level" message came on. I pulled over immediately, the engine seemed cool, I checked the level but it was hard to see. The engine normally runs at 197 almost all the time. However when I stop in traffic or pull a small hill, it may slowly climb up to 204-215 degrees. Then it will go right back down to 197 upon take off or normal driving.
I took it to the local dealer to have it checked. They pressure checked for leaks and couldn't find any. They said they added "a very small" amount of coolant but thought everything was normal.
It's pretty much done the same thing as far as the temperture goes (mostly 197 then up to 204-210 for short periods) The check coolant message has come on twice since then which was about 4 weeks ago, but then goes away and the coolant seems to be full.
This car is not my daily driver so I have only put about 500 miles on it since I purchased it. Also, there seems to be a slight smell of antifreeze in the enterior of the vehicle. It's so slight that I'm not even sure that's what it is but that's what it smell like to me.
I want to use this car on the highway for long trips but I'm a little afraid to until I have more confidence. I guess my main questions are.. 1. is the temp. range 197-214 normal(in cooler weather)....and 2. What about the "check coolant temp"message....and 3. How can I know for sure that what I'm smelling is actually antifreeze??
A little help from those more knowledgable will be greatly appreciated. This is my first "post" so be kind.
Remember that your engine uses DexCool coolant so if you add any be sure and use the correct coolant.

If you check the coolant when the system is cold the coolant should be about 1.5 to 2 inches below the pressure cap on the pressurized surge tank. That should be visible and easy to check. Only check it cold. If you get the low coolant message and the sytem is full then possibly the connector to the low coolant switch at the pressurized surge tank is loose or the low coolant switch inside the pressurized surge tank is failing or intermittant. No reason for the low coolant light to come on if the coolant is within 2 inches of the cap when cold.

possibly you have a minor seepage somewhere that is causing a loss of coolant?? Have the dealer add the GM coolant supplement pellets to the cooling system to seal any nuisance leaks that might be at a gasket interface or hose connection or due to porosity in a casting somewhere. That is what the sealant is designed for. Use 6 of the GM coolant supplement pellets or two tubes of the BarsLeaks "golden seal" powder .... they are the same substance and BarsLeaks supplies the Gm coolant supplement pellets. IMPORTANT: be sure the sealer is installed into one of the radiator hoses going to the radiator....NOT in the pressurized surge tank. Putting the sealer into the surge tank will not disperse it thru the system and can cause problems with plugging the hose from the surge tank to the water pump as there is little flow thru the surge tank and all the sealer at the initial installation could clog the hose. Just put it into the radiator hose and it will get dispersed properly. The sealant will not clog heater cores or anything and it is perfectly compatible with the DexCool. The factory installed the sealer on the assembly line when the vehicle was new...it probably needs replenishing by now if there is a nuisance leak somewhere.

budgarrett
01-13-04, 10:42 AM
THANKS TO WES/HEMHEM/MIKE/&BBOBYLNSKI!!

VERY GOOD INFORMATION IN ALL OF THESE. THE DEALER PRESSURE CHECKED ONCE, I THINK I'LL HAVE THEM DO IT AGAIN, FLUSH THE SYSTEM AND ADD THE PELLETS (SOMETHING I NEVER HEARD OF UNTIL READING POSTING IN THIS FORUM).
QUESTION? CAN THE DEALER TEST THE SENSORS (SENDING UNITS) OR DO THEY JUST REPLACE THEM?
AGAIN, THANKS FOR ALL YOUR REPLYS. YOU GUYS KNOW YOUR CADILLACS.

BeelzeBob
01-13-04, 01:10 PM
Take my advice and avoid the "flush". It is really not necessary and can lead to other problems if not done correctly. Just drain the system and refill with fresh 50/50 DexCool/distilled water. That is sufficient to get a fresh charge of coolant into the system. While the sytem is drained, disconnect the radiator hose and add the coolant supplement to the radiator hose. Make positively sure with the person doing the work that they are going to install the supplement in the radiator hose, NOT the surge tank.

Basically checking the coolant level sensor is done by making sure the sytem is full and watching the coolant level warning light. If the low coolant warning still shows up occasionally with the system known full then I would just replace the sensor...checking the connector first of course. "checking" or "testing" for an intermittant failure is pretty difficult and inconclusive sometimes. If the warning comes on with the system known full then it is pretty safe to assume that it is an intermittant.

budgarrett
01-13-04, 04:55 PM
Take my advice and avoid the "flush". It is really not necessary and can lead to other problems if not done correctly. Just drain the system and refill with fresh 50/50 DexCool/distilled water. That is sufficient to get a fresh charge of coolant into the system. While the sytem is drained, disconnect the radiator hose and add the coolant supplement to the radiator hose. Make positively sure with the person doing the work that they are going to install the supplement in the radiator hose, NOT the surge tank.

Basically checking the coolant level sensor is done by making sure the sytem is full and watching the coolant level warning light. If the low coolant warning still shows up occasionally with the system known full then I would just replace the sensor...checking the connector first of course. "checking" or "testing" for an intermittant failure is pretty difficult and inconclusive sometimes. If the warning comes on with the system known full then it is pretty safe to assume that it is an intermittant.

budgarrett
01-13-04, 04:58 PM
Thanks.....again, bbobynski! Am following your advise to the letter. I feel much relieved with a better understanding of the NStar, thanks to you and others.

Free Tibet
01-19-04, 11:39 AM
My 1999 DeVille is loosing coolant like yours. The dealer cannot find why. DON"T LET THEM REPLACE THE HEATER CORE. That doesn't stop the loss of coolant. So far I have had the heater core, radiator, water pump, cross hoses and the head ghasket replaced. I have also added the famous six tablets (although I smashed them and made a solution with cooant then put them in the resevoir). None of this has helped. Right now the entire resevoir is empty. THere are no visible leaks. I guess that means evaporation loss is the cause. But where and how. I called GM. They will do nothing to help. It's sorry about your luck. This is my third and last cadillac. Good luck to you.

zonie77
01-19-04, 03:29 PM
Free Tibet,
Soundds like almost everything was done. The only idea I have is the possibility of a cracked head. N* doesn't seem to have this very often and when we did the headgaskets on my brother's we didn't have the heads checked. Possibly the dealer did your headgaskets without checking the heads for cracks.
A pressure check would be a good idea even if it has been done before.

Free Tibet
01-27-04, 09:39 AM
I want to try adding BarsLeask into the heater hose on my 1999 DeVille. Are there any tricks to pulling the hose and replacing it? Do you need to put vasiline or something on the hose when replacing? Can the clamp brake? Anything else to be carefull of.

By the way thanks for all your post to my problem which is needing head gaskets. In my search for a mechanic I have learned that all the failures in my cooling system (radiator, heater core, water pump) were likely caused by some other problem, namely, a crack on the block.
Given the dealers reluctunce to work on the car maybe they suspect that to be the problem too. Ever hear of a MagnaFlux analysis that checks out blocks? Or should I just buy a new engine?
But right now I need to stop the high piteched squel coming for the engine when it gets up to running temp. I hope BarsLEaks stops it for the time being.



Have the dealer add the GM coolant supplement pellets to the cooling system to seal any nuisance leaks that might be at a gasket interface or hose connection or due to porosity in a casting somewhere. That is what the sealant is designed for. Use 6 of the GM coolant supplement pellets or two tubes of the BarsLeaks "golden seal" powder .... they are the same substance and BarsLeaks supplies the Gm coolant supplement pellets. IMPORTANT: be sure the sealer is installed into one of the radiator hoses going to the radiator....NOT in the pressurized surge tank. Putting the sealer into the surge tank will not disperse it thru the system and can cause problems with plugging the hose from the surge tank to the water pump as there is little flow thru the surge tank and all the sealer at the initial installation could clog the hose. Just put it into the radiator hose and it will get dispersed properly. The sealant will not clog heater cores or anything and it is perfectly compatible with the DexCool. The factory installed the sealer on the assembly line when the vehicle was new...it probably needs replenishing by now if there is a nuisance leak somewhere.[/QUOTE]

BeelzeBob
01-27-04, 03:25 PM
although I smashed them and made a solution with cooant then put them in the resevoir
This was an error. Read the instructions in the service manual. Put the 6 pellets (there is no need to crush them are anything) into one of the MAIN RADIATOR HOSES so the sealant will get dispersed thru the system. By design, the pressurized surge tank has little to no actual flow thru it, so, all that sealant that you poured in there is probably still there and not at the source of the leak. Just take the upper radiator hose off at the radiator, plop the six pellets in there, and put the hose back on. If you don't mind the mess, just take the hose off and put it back on. You'll spill some coolant but it is easily flushed away with plain water. Refill the system (just to top off what spilled) with fresh 50/50 DExCool/distilled water and away you go.

The idea of a "block crack" is not very realistic. I have never seen a Northstar block "crack" per se. There may be a minor casting flaw that eventually opened up due to thermal action over the years that allows coolant seepage but understand that , due to the design of the engine block, any coolant leak due to a porosity or cold shut in the casting or anything will leak to the external part of the block...i.e...someone should be able to see it. The dry valley of the engine is a possible location of something like this that would not be seen and the coolant would lie there and evaporate. The coolant supplement/sealer is very very effective at sealing this type of weep.

I would strongly suggest installing the supplement in the recommended manner (into the radiator hose) and drive the car. It is quite possible that the system made have had a slight weepage for a long time and the factory installed sealant has sealed it all this time. The sealant needs to be )properly) replenshed occasionally as it does get "used up" and ineffective over time. Replenishing it properly is probably all that is required.

How fast does the coolant drop? If the engine runs fine and the coolant loss is slow then just drive it and forget it. Keep the 50/50 mix in the trunk and add to the surge tank occasionally. Not the best circumstance but better than scrapping the car in frustration. It is still serviceable. Apply the dose of the supplement and drive it.

Before you give up on Cadillacs for this understand that BarsLeaks (who manufactures and supplies the supplement/sealer used in the Northstar at the factory) also supplies to just about every major auto manufacturer in the world...especially those with aluminum engines. Casting "flaws" and coolant weeps in aluminum blocks are something that is undesireable but the nature of the beast.....