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H6 sporadic over heat?

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Over the last three weeks the temp gauge will go all the way to the white line just under the red and stay before it drops and other times it will stay there. You can tell it is hot because the AC struggles to cool. I can tell when the tstat opens as it will cool down. It has been sporadic with no warning lights on the dash. The fans are working and the lower hose is new. It is hard to duplicate and sometimes it will cool right down when you drive and other times it will not. Seems like a sticking tstat. Wouldn't there be a dash warning light if it was getting that hot?
ps, I did search the forum and did not find an answer to my question.

Thank you,
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1995 2.2 Auto Legacy Sedan
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Discussion Starter · #6 ·
I will go ahead and get a oe tstat; I think that will probably do it as that is what my original thought was too.

Thanks for your help and knowledge,
 

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Discussion Starter · #8 ·
Well...darn the oe tstat change out did not due the trick and it is leaking around the housing now. Is their a certain position the tstat is supposed to be in? Seamed pretty straight forward and I was suprised to find it leaking. I did burp the system and noticed the bottom hose I replaced in June feels a little too soft. Wonder if the hose could be collapsing? but does not seem to be when I am inspecting it. I know the coolant is new. Fans are working. Any suggestions?
 

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Discussion Starter · #11 ·
Well after stepping away and posting my thoughts I went back to it and snugged up the bolts on the housing a touch more and the leak stopped. Hooray...There was a new gasket on the new tstat. I then washed through the radiator with a high pressure spray. I noticed that I now have two speed fans. I am positive they only ran at low speed when I checked it before. When the com[pressor for AC kicks on it brings both fans on high speed. When the compressor shuts off they go back to low speed. I am sure it must be a fan speed problem. They were not hitting high speed and now they are. It is also running fine and not over heating again.
 

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Discussion Starter · #13 ·
I hope you installed the wobbler on the up side when you put he thermostat in.

Sounds like you may have been low in coolant prior effecting the function of the ECT. The fans won't come on for high speed for cooling only until around 220. The ECT signal to the ECM controls when the fans change speed when the AC is off. The fans are high volume to start with, even on the low speed which should start up at 203.

If you have a scan tool you could watch the fan operation and speed in relation to what the ECT is sending. Of course, forcing it up past 210 will be a chore with a new Tstat and coolant.
I put the wobbler (never heard that one before) on the low side. What effect will it have? I would have thought the fans were temp controlled but they did come on high speed exactly when the compressor came on and went back to low speed exactly when the compressor shut off every time. I know the condensor for the compressor will cause the coolant temp to rise when the compressor is running but it is an immediate response. I will see how it goes. My wife is real good about letting me know when something is wrong with her car; She really pays attention.
Thank you all for the knowledge and advice:29:
 

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Discussion Starter · #15 ·
Back at it again. I am starting to think it is a temp sensor problem with the needle going in and out of the red so often. Tonight when I got home I let it idle even though it showed to be hot. Checked out the temps with a cheap harbour freight laser thermometer and found the hottest spot was 200. Top of the radiator was 160. I would say the average temp was 150-160. In no way did it seem Hot or make me have an Oh Chit moment. I believe the sensor is also shutting down the compressor when it is telling the computer it is hot. I did notice the driver side (oil leak on this side) ran 10 hotter than the non leaking passenger side. Where is the temp sensor located? I still have not flipped the wobler around. Also do the cooling fans shut down when it is in gear and you accelerate from a stop light? Also what is the best kit to use to check for exhaust gas in the anti freeze. I am not losing fluid at all but it was overheated at one time and the oil leak may be a warped head and that could be my problem. Sorry for the long read, I am getting frustrated.
 

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Discussion Starter · #20 ·
When the temp is approaching the red is the overflow taking on coolant? After the car sits overnight is the coolant full and up to the neck/cap of the radiator. When starting the car after sitting overnight do you hear a swoosh coming from the heater core or dash area? If so, there is air in the system. Burp the system again. This could also indicate HG failure. Someone mentioned cutting the over flow tube which is also a good idea. You want to make sure that is not making contact to the bottom of the reservoir. Make sure there is at least ½ inch between the angle cut of the hose and the bottom. Also make sure the reservoir is clean.
Yes the overflow does take water and the reservoir level rises and is clean. No swoosh. Spring also is facing correctly on tstat and the car is acting just like it was before.
The fan is off on cold starts.
I am leaning toward the sensor located on the leaking oil side of the head being messed up from being saturated in oil. I will try and get that valve cover replaced and do the plugs while I am in their.
How would I test the temp sensor/sender on this vehicle?
 

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Discussion Starter · #23 ·
Appreciate the information. I will try and check the temp and locate the sensor today. I will not be able to dive into this for a few weeks at least. I will see what the temp is reading and post up. Hope it is not the head gasket and it holds up.Thanks again,
 

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Discussion Starter · #24 ·
Well after checking it out today and seeing bubbles in the over flow I think it is the head gasket. This is very unwelcome news as I blew the head gasket on my 3.0 Ranger pick up 3 weeks ago. I keep up with all maintenance on my vehicles regularly and this is very frustrating. Guess this is what I get from buying and driving only used vehicles. I am gonna have to step up my game and do this myself as there is no way I can afford this. Sucks for me right now, think I will go drown my sorrow. Tomorrow will have to be a better day.Thanks again for all the good info everyone has provided.I have to wonder if the ethanol we are being forced to use is what the underlying culprit of my problems are and the rest of my motors are on borrowed time...
 

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Discussion Starter · #28 ·
no PM huh?

well, you could drive to his shop and speak with him I guess.
True or even call him on the phone. His time is valuable and I do not want to waste it or take it up if it is not necessary. Off time is even more valuable as there is never enough, especially when you fix things for a living. Throw in a hobby or two with a family and time and money are in short supply.
I think we can work it out though, thank you for the suggestion ;)
 

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Discussion Starter · #37 ·
Thanks for the explanation.

Once again, your understanding and troubleshooting techniques are raising the bar -- thanks.

Oh, and about the funnel, I've been considering it for some time; now will get it.

Sub Fish: If you do get to work on the engine, would you consider making it a project thread, perhaps in the DIY sub-forum?
That would be an interesting idea. Thanks cardoc for posting this up. This will be a great way for my son and I to learn together. We will also be getting his future high school car built. Subarus are new to me and I am learning through the school of hard knocks as usual. Cardoc is really helping me out on this and I do appreciate it. I drove this car back and forth from Austin to Houston twice in December. Unbelievably stout motor.Thanks again,
 

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Discussion Starter · #40 ·
The engine is in. I've been running slow. Feeling crappie.

I took a video but its taking forever to upload. Just check my channel in probably 20-30 minutes. The Runt and I are delivering the car and his old engine, so we need to split.
I would really like to thank Cardoc and the Runt for getting this done. They went above and beyond to get the car back to us in one day, returning it in much better shape then what it was recieved in. Cardoc is an excellent technician and he will be seeing more of me in the future. Nice to see a real Pro at work.
Thanks again,
 
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