Need a little help with a coolant issue

[reeze]

I have a '95 Legacy FWD, bought used about 3 yrs ago. It has about 133K on it. A few days ago my check engine light goes on, I'm concerned but the car seems fine so I'm thinking it's a bad sensor.

 

Last night I'm driving and happen to glance at the temp gauge, it's nearing the top of the scale. I turn the heater on and set the temp to hot; the needle moves down to the middle. After a few minutes, though, the air is blowing cold and the needle starts moving back up. After a minute or two more, though, the air starts getting warm again and the needle moves down to the middle. I made it home without further incident.

 

This morning I check the coolant reservoir and it's empty. I have never been motivated to fill or even check the coolant level in this car since it ALWAYS ran cool (needle just under the middle). Yes, my bad.

 

One thing is that I have no owner manual. I remember reading somewhere that you add coolant to the reservoir, NOT by opening the cap and pouring directly into the radiator. Am I right? Is there anything else I need to know about this simple procedure?

 

Now the question is if this is a new problem or just my lazyness in checking the coolant level. The oil looks OK, but I haven't yet checked to see if there's steam coming from the tailpipe.

 

Hoping this is just the thermostat and low coolant level...any advice is appreciated, thanks!

[porcupine73]

On the Suby's you don't have to add the fluid to the overflow tank, just pour it in the radiator cap opening and make sure to get out any air bubbles. There are some fords and others that say to add coolant only to the overflow tank, maybe to limit their liability if you take the radiator cap off and get burned.

 

Hopefully your issue is just that you were low on coolant, but if you haven't changed it in years then it's time for a drain and refill anyways, at which time you can put in a new thermostat and gasket, this isn't a very difficult job. There's many posts on how to do it and how to get out the air pockets.

 

You might be losing coolant somewhere for it to get low in the first place so keep an eye on the level in the overflow for a while afterwards. Anyway I wouldn't drive it anymore until you at least make sure the coolant is full; otherwise you're risking warping the heads if there's no coolant there.

[Megell]

I have a '95 Legacy FWD, bought used about 3 yrs ago. It has about 133K on it. A few days ago my check engine light goes on, I'm concerned but the car seems fine so I'm thinking it's a bad sensor.

 

Last night I'm driving and happen to glance at the temp gauge, it's nearing the top of the scale. I turn the heater on and set the temp to hot; the needle moves down to the middle. After a few minutes, though, the air is blowing cold and the needle starts moving back up. After a minute or two more, though, the air starts getting warm again and the needle moves down to the middle. I made it home without further incident.

 

This morning I check the coolant reservoir and it's empty. I have never been motivated to fill or even check the coolant level in this car since it ALWAYS ran cool (needle just under the middle). Yes, my bad.

 

One thing is that I have no owner manual. I remember reading somewhere that you add coolant to the reservoir, NOT by opening the cap and pouring directly into the radiator. Am I right? Is there anything else I need to know about this simple procedure?

 

Now the question is if this is a new problem or just my lazyness in checking the coolant level. The oil looks OK, but I haven't yet checked to see if there's steam coming from the tailpipe.

 

Hoping this is just the thermostat and low coolant level...any advice is appreciated, thanks!

 

 

I would visually check closely for leaks, but it sounds like maybe it was just time to check the antifreeze level and top off. I would just fill it back to upper level and keep a close eye on the gauge. It it still heats up, you may have to "burp" the system to clear the air out of the system.

Ummmm,....... you may want to check your oil level while you are at it.

Mike

[lpasco]

:-\ not a good thing with subarus with getting hot. If it blew cold air and was getting hot, it proubably has a pluged thermostat or a bad water pump.

 

First thing i would do is add coolant to the radiator and add coolant to the resivor to the cold mark. THey both need fluid in them.

 

When was the last time you checked the temp specs on the coolant? Change in temp outside could cause these problems, but proubably not the loss of water.

 

Check the oil level and make sure it isent filling up highter with water. It is very posable that you have a small coolant leak and it never caused problems untell it just got below that level where it causes problems. (sounds wered but ive noticed that it can get low but there is a point where it just hits).

 

Once filled with coolant, check the temp. if it stays the same, start looking for leaks. If it goes up again...... have fun. THe thermostat is right under the water pump and only has 2 bolts that hold it in. CHange that and all of the coolant and try it again. If that dosent fix it, consider doing a timming belt and water pump. (when was the last time you changed your timming belt?)

To change the water pump you have to remove the timming belt and if you remove the timming belt, you might as well replace it.

 

It is possable you have a bad sensor and you can change it to see if it makes any difference. THe sensor is right under the egr valve on the pass side on the little water duct above the block itself.

 

these are just the steps i would take to fix the problem.

[reeze]

Thanks for the quick reply! So I just open a drain plug at the bottom of the radiator, empty it out, then refill? I remember seeing "flush kits" in parts store that let you attach a garden hose and flush out the engine. Do those still exist, and would it be preferrable?

 

Now here's another stupid question: I have no antifreeze so I'm going to have to fill with water just so I can drive to the parts store. My tap water is very hard, can this harm the engine? I do have some bottled water on hand.

 

On the Suby's you don't have to add the fluid to the overflow tank, just pour it in the radiator cap opening and make sure to get out any air bubbles. There are some fords and others that say to add coolant only to the overflow tank, maybe to limit their liability if you take the radiator cap off and get burned.

 

Hopefully your issue is just that you were low on coolant, but if you haven't changed it in years then it's time for a drain and refill anyways, at which time you can put in a new thermostat and gasket, this isn't a very difficult job. There's many posts on how to do it and how to get out the air pockets.

 

You might be losing coolant somewhere for it to get low in the first place so keep an eye on the level in the overflow for a while afterwards. Anyway I wouldn't drive it anymore until you at least make sure the coolant is full; otherwise you're risking warping the heads if there's no coolant there.

[lpasco]

water wouldent harm your engine as long as the outside temp is ok. It i guess could harm it if the car gets hotter then something like 250 degrees. If you drive it watch it like a hawk.

 

They do still sell the flush kits, but in my opinion they arnt that effective. I would just pull the bottom radiator hose and let it drain. There is i think a little plug on the pass side of the car on the radiator, but i dont think it drains that fast.

[reeze]

Wow, three other replies while I was replying to porcupine73! Thanks all.

 

>>When was the last time you checked the temp specs on the coolant? Change in temp outside could cause these problems, but proubably not the loss of water.<<

 

I don't know what you mean by "check the temp specs on the coolant." I live in the New York area, and just the last two nights it has been getting colder (we had our first frost warning two night ago).

 

>>Check the oil level and make sure it isent filling up highter with water<<

 

Oil level doesn't seem high and there's no overt evidence of water (i.e., "milkyness").

 

>>when was the last time you changed your timming belt?<<

 

Changed this past summer.

 

>>It is possable you have a bad sensor and you can change it to see if it makes any difference. THe sensor is right under the egr valve on the pass side on the little water duct above the block itself.<<

 

Since I only have a vague idea of what an egr valve looks like, I'm not able to see this sensor. I followed the upper radiator hose to the engine inllet, it passes under the manifold and everything looks pretty inaccessible--unless I'm looking at the wrong spot. I assume the sensor is a dealer part too, correct?

[Manarius]

I think he means the Coolant Temperature Sensor. I have a picture here of what you should look for:

http://www.discens.org/DSCN2628.JPG

 

It's the brown plug that is the coolant temp sensor (if you look at the intake from the back, it's on the passenger side). It's about $27 from autozone.

 

Hints for replacment (although, I don't think this is a coolant temp sensor case, but it never hurts to replace it):

 

Deep socket so you don't have to work hard at getting it out.

Park your car downhill (so the engine is the lowest point) to minimize coolant leakage.

[reeze]

Thanks Manarius!

 

It's behind the blue thingie, right?

 

I think he means the Coolant Temperature Sensor. I have a picture here of what you should look for:

 

 

It's the brown plug that is the coolant temp sensor. It's about $27 from autozone.

[jon38iowa]

water wouldent harm your engine as long as the outside temp is ok. It i guess could harm it if the car gets hotter then something like 250 degrees. If you drive it watch it like a hawk.

 

They do still sell the flush kits, but in my opinion they arnt that effective. I would just pull the bottom radiator hose and let it drain. There is i think a little plug on the pass side of the car on the radiator, but i dont think it drains that fast.

I agree with the Above! One time I opened the drain and ( because of rust whatever) it would not close; My mechanic told me most shops don't touch it,

but instead simply remove the front of lower radiator hose.

John

[reeze]

simply remove the front of lower radiator hose.

That is a very good tip, thanks! I could have gotten into some trouble.

[porcupine73]

Sounds like a plan. I would not run just plain water for any longer than is absolutely necessary because water does not have any corrosion inhibiting properties. I would not use a garden hose to even flush the system; distilled or RO water is preferred, especially if you use a phosphate containing coolant, (Subaru does specify) which can precipitate out with hard water. (That's why european coolants are phosphate free - hard water is common there).

[reeze]

Well, I filled the radiator with about 1/2 gallon of bottled water (actually I poured some of that into the overflow tank). Then I ran the engine, waiting for the thermostat to open up, thinking I would add more. It never seemed to happen, and the temp gauge needle went to it's old spot, right under the middle, and stayed there.

 

I took the car out--drove to the auto parts store and bought a thermostat & some antifreeze. Then I drove on the highway for a bit to go to a shopping center, then back home. The needle never went beyond the middle of the range, and the car seemed fine--no abnormal smell, no steam coming from the tailpipe. Maybe I dodged a bullet?

 

Of course I'm still going to do the thermostat, empty the radiator and put fresh water & antifreeze in.

 

Thanks for the tips about the water, I'm glad I didn't use my tap water!

 

One thing--the "check engine" light is still on. Gotta get that checked, I guess.

 

Sounds like a plan. I would not run just plain water for any longer than is absolutely necessary because water does not have any corrosion inhibiting properties. I would not use a garden hose to even flush the system; distilled or RO water is preferred, especially if you use a phosphate containing coolant, (Subaru does specify) which can precipitate out with hard water. (That's why european coolants are phosphate free - hard water is common there).