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low coolant/high temp light intermittent flashing


my94baby
09-26-2008, 12:26 AM
Hi lovely Auto Forum people:

I see that a couple other people have had this. My coolant level is fine, the engine doesn't seem to overheat (unless maybe that sensor is wrong too?), and the coolant/temp light only flashes every so often.

For example, it may flash a bit if I go up a small hill, or when I accelarate from a stop, and then it will go off after a few seconds.

I am not knowledgeable about cars, so my first question is: is something really bad going to happen if I ignore this? I don't have much money and maybe I should just wait?

Second, could it be related to my recent boneheaded maneuver in leaving off my oil cap? I know I should get this cleaned, or at least change the air filter, as my mileage seems a bit lower since this happened. (Speaking of this, for what it's worth, when my oil cap was off, none of my warning lights went on! I only found out the next time I checked the oil and the stick came up CLEAN. Yikes.)

Third, could this be related to my recent replacement of the alternator?

Or is that other stuff just normal for a car this age?

I have to say, it's been pretty good to me. But now I am wondering what major thing will break next, and if maybe somehow I can prevent it. It's got about 124k miles on it.

I appreciate your help. I am really impressed by the people on this forum. Knowledgeable and helpful. Is this a great country or what???

Clunkers
09-26-2008, 10:42 AM
Same exact thing happens with mine: If I step on the gas or going uphill.

I would say it's not something major to worry about at least right now.

I have a 1997 SL2 120+K on it. Bought the car 14,000 miles ago and my coolant level/engine temp light has been flashing randomly for a good 10,000 miles (It's almost a joke at this point - I've done everything to flushing the system and changing out sensors). Temp runs almost 1/2, and I rarely start to overheat.

If you read other people's posts, this is a very Common issue with our wonderful Saturns.

In one post I read, a mechanic was talking about how sensitive the sensor's are in these cars, and if the coolant level is just a tiny bit below (almost unnoticable) it will set that light off.

Maybe just add a little coolant first and see what happens. (The incline of a hill and movement of punching the gas may just be enough to move that coolant around and set off the sensor)

Worth a try before diving in deeper.

my94baby
09-26-2008, 06:41 PM
Thanks for the reply!
Yes, I guess I'll just watch and see for a while. I think the level of coolant is okay.

denisond3
09-27-2008, 11:07 AM
Hopefully someone who really knows will answer. The low coolant & high temp light is the same light. It means one thing if its on steady - and I think 'steady' means the coolant is overtemp. If blinking I believe it meas the coolant level in the plastic tank is low, or the sensor in there thinks its low.
Neither of our Saturns (92 & 98 SL2's) is in the driveway or I would look in the Owners Manual, which is where this is explained.
The 98 Saturn was giving us the occasional blink, and though the coolant level didnt seem low, we added some - - and it hasnt blinked for a couple of months.
So I think could be a combination of the coolant level being slightly low, or the sensor being coated with crud and not sensing properly.

my94baby
09-29-2008, 05:09 PM
Yes, I hope you're right. I opened the lid and eyeballed the fluid and it looked okay, so I guess that means the sensor is not working.

RC1488
09-30-2008, 01:01 PM
Clean your fluid resiviour. Remove it and clean it with soap and water. As mentioned before, the sensor is very sensitive. Some more than others. New sensors can be bought, however they come with a new resiviour. You cant get them seperate.

No this will not hurt your car.

And no leaving the oil cap off doesnt hurt your car. Just makes a mess.

PS...124K miles....your saturn is a baby still. Teenager in the saturn world :)

my94baby
10-02-2008, 03:06 PM
Thanks!

denisond3
10-04-2008, 07:54 AM
I wonder if you could clean that reservoir it by draining the coolant out, or syphoning it out. Then using a spray can of brake-cleaner (which is mostly a water and alcohol mix) to clean in it. The ones I like come with a little red tube, so you can squirt the cleaning solution into small spaces. There is a fair amount of pressure in the cans too. Then you would want to either syphon that cleaning solution out (and the loose crud with it) or rinse it with the spray from a garden hose. This would work even better if the reservoir was removed from the car and turned upside down for draining crud. This is what I will try the next time that light begins to come on.

Other topic: Our 98 Saturn sl2 has 150,000 miles on it and uses a quart of oil each 1200 miles. I put new piston rings in the engine of our 92 Saturn SL2 that had 128,000 on it and was guzzling oil. Now it goes 4000 miles between oil changes, without having used more than half a quart of oil.

RC1488
10-04-2008, 10:07 AM
If your going to drain the coolant from the resiviour, might as well just remove it and clean it inside. Soap and water work best.

Saturns burn oil bc of faulty oil ring designs. when you replaced your cylinders im assuming you replaced the rings also. Problem fixed.

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