Normal Engine temperature/High engine temperature

[98redaurora]

Hey guys! Well today I was driving my grandma around and as we were getting back to her place. I glanced down and noticed my temp was at 240! Is this normal. It was like 85 outside and A/C on. 64,000 miles.

I drove it a little more, I got to 220, but never over that in this short trip. So overall, my temp was from 200 to 240.

Could this be the start of a head gasket problem.
What should I do?

[wireless]

Head gasket issues don't usually develop unless you let it overheat; overheating is what will lead to it!

As far as what you should do... turn on your AC, make sure your fan comes on!
Check your coolant levels.

Was this in stop/go traffic, or highway?

[98redaurora]

Stop and go.
Just checked coolant. About 1 inch low, after engine had been sitting overnight.

[wireless]

Hmm.. Are you using a good mixture of coolant / water?

[lkraft92]

240 is a bit alarming. When i drive city, i will generally hit 220, but i dont think ive ever hit 240. Definitely need to fill the coolant and check it regularly. Cars this old now will start to leak coolant. I gotta top off my coolant every couple months.

Sent from my DROID RAZR using proboards

[sall]

Are you going solely by the gauge or by a scantool?

Aug 23, 2012 11:22:05 GMT -6 lkraft92 said:

I gotta top off my coolant every couple months.

Really? Better pop in some coolant tabs and start the investigation.

[98redaurora]

I don't think it was quite 240 maybe 230. I am going solely by the gauge. If it hit 240 wouldn't it throw a code or something? Regardless. I am thinking it is the orignal coolant in the car. I need to go back through the records I have and see.

Checked oil. Still looks new. I changed it a few weeks ago...
I about to go drive it. So I'll keep an eye on the gauge. I realize this car doesn't have a grill. But should'nt it stay about 200ish always?

[lanceslambos]

you won't see 200 unless you have cooling mods but 240 won't throw a code. i honestly suspect a leaky coolant cap. head gaskets should be fine. perhaps a fuse on your fan. a/c kicks fans on. someone else mentioned it too. back to basics - check coolant with a ball gauge and use distilled water.

[lkraft92]

Hey lance, when im on the highway, on a nice day, i almost never go over 200 and i havent done any cooling mod. If i start going over 200, i know something is up.

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[wireless]

Exactly. Mine rarely even went above 200-205 in city driving..

[RCA1186]

I'll third that. No "cooling mods" on either aurora and both stay(ed) right below the 200 mark (going of the gauge that is) and only on really hot days and lots of stop and go traffic did they hit 225 and near never higher than that.

240 is a bit high, #1 change your coolant if you're not sure of its age. Get some dex (or green whichever you prefer just dont mix em!) and some GM cooling system tabs from a dealer (I paid like $6-7 for 6 of them) I also usually change the thermostat when I do the coolant, its not required though, I do it for peace of mind haha.

Also, check and make sure your air dam in front isn't obstructed or moved around. (once while driving home I was getting very high temps and didn't know why, later on I discovered a plastic bag smashed up in there)

[98redaurora]

Aug 23, 2012 18:52:23 GMT -6 RCA1186 said:

I'll third that. No "cooling mods" on either aurora and both stay(ed) right below the 200 mark (going of the gauge that is) and only on really hot days and lots of stop and go traffic did they hit 225 and near never higher than that.

240 is a bit high, #1 change your coolant if you're not sure of its age. Get some dex (or green whichever you prefer just dont mix em!) and some GM cooling system tabs from a dealer (I paid like $6-7 for 6 of them) I also usually change the thermostat when I do the coolant, its not required though, I do it for peace of mind haha.

Also, check and make sure your air dam in front isn't obstructed or moved around. (once while driving home I was getting very high temps and didn't know why, later on I discovered a plastic bag smashed up in there)

I am going to do this. I probably will be changing the thermostat and changing coolant. I checked the air dam, its fine. Drove it today, it never went above 200.

By the way, THANK YOU GUYS! It is so comforting to know that when I have issues with my car, that all I need to do is post on here, and almost always a solution or an answer is found. You guys rock!!!

[nelson480]

According to someone here the first notch past 200 is 220, not 240. I have yet to check this with my scan tool to verify but i have no reason to doubt that person.

[RCA1186]

Well when you look at the gauge to me it looks like 25 degree increments which IMO makes the first notch past 200degrees = 225 lol I'll have to scan tool check it one day

[groomlaketested]

Kinda of a thread hyjack, but what is the overall difference between the 15psi cap and the 18psi cap. And if anyone says 3lbs of pressure there gonna get smacked )

[wireless]

3lbs of pressure...


If I recall correctly, Lance has stated that it raises the boiling temp. of the coolant roughly ~10 degrees per psi... so it would raise the boiling point of it by 30F roughly, according to this, which means that more coolant is running through on it's own, instead of air that's coming from the boiling water.

[danelover100]

My car has no cooling mods and runs at 190 to 200 all the time. If I get in to stop and go traffic it goes to the first notch above 200 and stays there. I have never heard my fans run on this car. I know they work though because I tested them when I replaced the radiator.

[sall]

"For every 1lb of pressure the boiling point of water goes up roughly 3 deg.. However system components in the cooling system are designed to work in the 15-16lb range. By installing a higher pressure cap you run the risk of blowing a component such as the rad, gaskets or weakened hoses. I don't recommend doing that since with a 50/50 mix your boiling point is around 265 deg anyway. Most GM cars/light trucks operate a 15lb cap. The Stant replacement will cross to a 16 but 1lb is not significant. As the other post stated it will not improve cooling, only raises the boiling point."

Quote from Cadillac forum because I had it bookmarked sometime ago when my cap was not operating properly and I replaced, but not before doing research. I run the 15 psi cap. I do not recommend 18 psi cap. The cross threading the reservoir threads with aftermarket cap is a myth. 9/10 cross threaded threads are user error.

[wireless]

Well then, I suppose I was way off. lol

[sall]

Fresh coolant, new thermostat and all air dams/reflectors in place with 87* ambient temperature in stop and go traffic the instrument cluster temperature gauge stayed a hair below 200* degree mark and CarPC scantool never rose above 197*.

[98redaurora]

So i did hit 225 yesterday. So I'm going to get a new thermostat, and a coolant flush.

[Greg K]

My 1997 runs under 95 Celsius (200 F) in all kinds of driving up here in Canada.
I'm starting to feel lucky !
My mileage is 165 K (102,000 miles).
Dr K

[55624096]

Your engine should run at about 200 degrees, The stock thermostadt is a 180 degree unit. The first thing I would do is replace thermostadt. If yours is origional it is probably failing from old age. Don't wait since when it completely fails it will stay closed and you will overheat, maybe pull the head bolds. Thermo is easy to replace 1/2 hour and only should cost less than $20.00.

[98redaurora]

That is what I am planning on doing. However, since in hasent gone above 200 in a few days (its kinda of a random thing when it goes above), I would say that I have a failing thermostat.

[lanceslambos]

Aug 24, 2012 9:05:33 GMT -6 wireless said:

3lbs of pressure...


If I recall correctly, Lance has stated that it raises the boiling temp. of the coolant roughly ~10 degrees per psi... so it would raise the boiling point of it by 30F roughly, according to this, which means that more coolant is running through on it's own, instead of air that's coming from the boiling water.

nope! it raises it 10 degrees overall not 10 per pound. 3.3 degrees per pound x 3 = 9.9 degrees (or 10)

and sall if you go to a dealership for replacement they will give you an 18 psi cap!

[98redaurora]

Ok, so I flushed the coolant system myself. Installed a new thermostat. I am working on getting it to take all of the coolant.

I drove it for a little bit and it never went above 205. I still have a few more quarts to put in. We will see if I can do this without running into problems.

Does anyone know at what temperature the fans kick on? I never really got mine to turn on, when filling it with coolant. However, they do turn on when the A/C is on.

Thanks,
98redaurora.

How can such a nice car, have so many problems, gosh....

[sall]

The PCM will command fan operation when:

Low Speed Fan Operation

Engine coolant temperature exceeds approximately 106°C (229°F).
Transmission fluid temperature exceeds 150°C (302°F).
A/C operation is requested.
After the vehicle is shut OFF if the coolant temperature at key-off is more than 151°C (304°F) and system voltage was more than 12 volts. The fans will stay ON for approximately 3 minutes.


High Speed Fan Operation

Engine coolant temperature reaches 112°C (234°F).
Transmission temperature is more than 151°C (304°F).
When certain DTCs set.

The fans will switch from low to OFF when the coolant drops below 102°C (216°F).

The fans will switch from high to low (except DTCs set) when the coolant drops below 106°C (229°F).


Check out Bob's Deluxe Cooling Fan Mod in the stickies.

[98redaurora]

Thanks sall!!! Very useful information..

[98redaurora]

Ok, so if normalish is around 200. Why do they have the fans turn on at 229 and hi speed at 234??

[wireless]

That's a VERY good question, lol.