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Giggle Squirt
01-02-2009, 07:17 PM
I have a subaru and i think the thermostat might be going on it... when i am driving on the highway around 100kmh (mostly on I75) the inside of the car will start to fog up because the heat output will go down. i have seen the temp guage on the car gradually dip a bit once i reach the speeds on the highway then once i am back in the city driving at the city speed the inside will unfog and the temp will go back up to operating temp. NOW i have only owned the car since dec 6th and i don't hve any history on the car as to when the thermostat was changed last and i did do a flush on it on the 6th. also when i apply the brakes the blower will change the output of air.. and then when i accelerate the blower will increase the air. Yes i have checked all fluid levels. This happend before in my bf old civic but it was a civic so i didn't think nothing of it.

puppy
01-02-2009, 07:54 PM
could be also a heater core on it's way out..
sometimes when heater cores go they do that too..

Barry Morris
01-02-2009, 10:10 PM
A leak heater core WILL fog the windshield, but you'll also have a sickly sweet smell of antifreeze, or rub your finger in the vapour and see if it's sweet on the tip of your tongue.

Those symptoms make me think of a vacuum leak affecting the heater control operation. The brakes also use vacuum, so the blower sound change could be caused by the leak. Maybe. Possibly something more serious, like a head gasket problem. Is the antifreeze level dropping at all??

Giggle Squirt
01-02-2009, 10:22 PM
the rad level has stayed up. No head gasket prblem. It is not a fog like a heater core fog. i have seem many of them.. imagine your driving your car with the heat off and the windows fog over.. then you turn on the deforst and they clear that is what is happening. I don't have the smell of antifreeze and believe me after blowing a headgasket before i know what antifreeze smells like. I thought my heater was electronically controlled not vacuume controlled. hmmm will have to look into it i guess. what is the difference between vacuum controlled and hydraulic controlled brake boosters.

Barry Morris
01-03-2009, 10:36 AM
Not sure about your car, but most cars have vacuum assisted power brakes. If there's a leak, stepping on the brakes MIGHT cause the vaacuum to drop so far that one of the vacuum powered vent doors to the defrost closes.
Listen for a whistling noise under the hood or dash.

Giggle Squirt
01-03-2009, 11:14 PM
well.. i have determined why the inside fogs up at hight speeds.... i have frameless doors and 2 sunroofs in my car and well the air is comming in through the doors and some from the sunroof. as for the temp dropping i think it is just because the engine compartment is so open and lots of air flow... I took it for some test runs today.... and it is a vacuum assisted booster :P

Barry Morris
01-07-2009, 10:06 PM
well.. i have determined why the inside fogs up at hight speeds.... i have frameless doors and 2 sunroofs in my car and well the air is comming in through the doors and some from the sunroof. as for the temp dropping i think it is just because the engine compartment is so open and lots of air flow... I took it for some test runs today.... and it is a vacuum assisted booster :P

Somthing just occured to me. Does this car have a recirculating air switch?? This switch chooses either inside or outside air as a source for the heater. It CAN help the inside warm up quicker, BUT, if you leave it closed, using inside air, the moist air inside fogs the windows. You have to use outside air to warm the car.

Maybe?? Let us know,please.

Giggle Squirt
01-07-2009, 11:55 PM
yes it does have a recirculating switch which is set to draw in the air from outside. My car is full of air leaks which i have found so far. the glass is not seatingright on the rubber that is supposed to seal them.... aslo the car has two sunroofs both of which open. Their is alot of moisture in their when i opened them (the covers that close out the light) this is whati am talking abot ... http://www.youtube.com/watch?v=s8syaTmDCo0