Hi, I have a 95 Civic LX. About a week ago i looked down and saw it was redlining as far as engine heat. I also noticed that about that time, i was no longer getting heat in the car but AC like cold air. The other night I replaced the Thermostat, flushed the system, pressure checked the radiator, checked head gaskets, and replaced the Radiator Fan Senson on the thermostat. Then as im delivering pizza's today (I work at papa johns ) shoom there it goes flying up again....I went and jumped the cooling fan cable so the radiator fan is constantly on but this doesnt seem to be helping (I dont think the fan was ever coming on anyway)....Any ideas would be GREATLY appreciated. Thanks

 

make sure you have got all the air bubbles out of the system.. if a bubble passes past the housing it will register as being very hot because the steam is way hotter..sometime the steam pocket will stay there for long periods of time causing it to look like your overheating when its really not

 

Mind telling me how i go about getting the bubbles out?

 

If your not getting heat inside the car, it's most likely not air or a failing temp sensor. My girlfriend had a Subaru 2.5GT that actually had a leaking water pump. It ran fine but was slowly loosing coolant until it finally reached a point where it was too low to function and the car overheated. I ended up putting a bottle and a half of that pre-mix antifreeze in it just to top off the radiator and get it home. If you've got a small coolant leak you could have a similiar situation. Have you tried topping off the system to see if there is any fluid missing? Can you please deliver me some large plain cheese pizza's too (there's no Papa John's within delivery range of my place and I miss it so much).

 

The heat works fine, until it starts to overheat, then it becomes cold, then the needle will fall a little and i notice more heat.....still think this could be a coolant leak....I check the reserve tank and the levels havent changed.....

Thanks for any additional help

 

yah thewre is a nut on the top of the thermostat housing you need to start the car break that nut loose and there is a little nipple on the top of the nut that the coolant will start to come out of wait til all the air is out then tighten it up add a little more coolant do it again and you should be fine..also the reason your gettin cool air is from the same reason..but at a different sensor located near the back of the intake manifold..as long as you get all the air out you will be fine..i had the exact same problem two weeks ago..cold air and all

 

I just looked, there is no nut on the thermostat housing...there is however a nut
right b4 it runs into the engine from the radiator, i bled that and still no luck?

Please help

 

sounds likw a bad head gasket to me... or you have air in your coolent lines...


drain out the coolent then fill it back up with the car running (do it from the radiator not the reserve tank) when the car heats up the thermostat lets the coolent into the head and you will see the coolent bubble form the radiator at that point pour in more fluid unitl it tops off... solves the air bubble problem