Strange overheating issues '95 Legacy sedan

[Nicholas.Conrad]

Friday night my check engine light came on, but I experienced no change
in the feel of the car, performance, or engine noises. The car
operated without change for several hours until I was driving home,
then it began to overheat. I pulled over the car, checked all fluid
levels (they looked fine), and when I got back in the car the check
engine light was now off. The overheating issue persists, however.
The needle is usually just below the half-way mark when the engine is
warm, but it begins to creep up now, coming to rest at about 85% to the
max mark. If I rev the RPMs to 3.5-4 x1000, the needle will
immediately fall down to about half way, and then begin creeping up
again (probably takes less then two minutes to go from half-way to
85%). Sometimes the car runs fine for hours before this starts,
sometimes it starts minutes after the car warms up. Sometimes it will
be overheating, and suddenly cool down and be fine. I just noticed
this last night, and it may be coincidence, but it seems that as long
as my heater is on full, the engine will be cool, and if I turn off the
heater, or move the slider all the way to cold, the engine overheats
again. While the heater is on, the air coming out is hot (possibly
hotter then it was before, but maybe I'm imagining that). It seems
like the kind of problem you would remember if you've run across it
before, so I'm hoping someone can help. I had the water pump and
radiator hoses replaced about a month ago.

Thanks.

 

[jfindlay]

engine light was now off. The overheating issue persists, however.
The needle is usually just below the half-way mark when the engine is
warm, but it begins to creep up now, coming to rest at about 85% to the
max mark. If I rev the RPMs to 3.5-4 x1000, the needle will
immediately fall down to about half way, and then begin creeping up
again (probably takes less then two minutes to go from half-way to
85%). Sometimes the car runs fine for hours before this starts,
sometimes it starts minutes after the car warms up. Sometimes it will
be overheating, and suddenly cool down and be fine.

Perhaps your thermostat is having problems. I'm no expert and this
could be wrong, but it is something you can check if no advice more
material is offered.


Justin

 

[Carl 1 Lucky Texan]

Friday night my check engine light came on, but I experienced no change
in the feel of the car, performance, or engine noises. The car
operated without change for several hours until I was driving home,
then it began to overheat. I pulled over the car, checked all fluid
levels (they looked fine), and when I got back in the car the check
engine light was now off. The overheating issue persists, however.
The needle is usually just below the half-way mark when the engine is
warm, but it begins to creep up now, coming to rest at about 85% to the
max mark. If I rev the RPMs to 3.5-4 x1000, the needle will
immediately fall down to about half way, and then begin creeping up
again (probably takes less then two minutes to go from half-way to
85%). Sometimes the car runs fine for hours before this starts,
sometimes it starts minutes after the car warms up. Sometimes it will
be overheating, and suddenly cool down and be fine. I just noticed
this last night, and it may be coincidence, but it seems that as long
as my heater is on full, the engine will be cool, and if I turn off the
heater, or move the slider all the way to cold, the engine overheats
again. While the heater is on, the air coming out is hot (possibly
hotter then it was before, but maybe I'm imagining that). It seems
like the kind of problem you would remember if you've run across it
before, so I'm hoping someone can help. I had the water pump and
radiator hoses replaced about a month ago.

Thanks.

I'd say its possible the cooling system was not adequately 'burped' when
refilled after the work was done. Also, I suppose its possible the
thermostat is failing somehow, though it seems weird.

Have the cooling system rechecked by someone very familiar with Subarus.

Carl

 

[Jack Countryman]

You did check to be sure you have coolant up to the proper level? Is the
radiator obstructed in some fashion? (If having the extra temperature
exchange of the heater on high helps, it would seem the main radiator is not
exchanging heat well...either blocked, fan not running (belt(s) OK?), fan
blades missing or bent, or something like that?

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