My car is completely topped off with antifreeze and the fan is working and everything but when im sitting with my car running at an idle my car starts to overheat (kinda sucks at red lights) but when i can on it the heat guage instantly droppes back to normal. i was thinking it has something to do with the thermostat but im not too sure. if so how much does this fix cost

 

Thermostat could be needing replacement, or maybe the coolant system needs to be bled.
(lol.... "heat guage")

 

thanks for the super fast reply. how do i go about bleeding the coolant system, and if its not that how much is a thermostat replacement

 

It's like ... under $20 for a thermostat and thermostat gasket. And to bleed, on your Civic at least, just open the radiator cap and let the engine run. There's no bleed screw. Just be sure to top the radiator off if needed. Pull the temp thing on your climate control to full heat and let it run until the radiator fan turns on and off twice.

 

just replace the thermostat, its easy and cheap. The lower radiator hose might be really hard to get off so you might have to cut it and buy a new one. Check to make sure you can get it off before you go buy the thermostat so you dont have to make two trips to the auto parts store. GL

 

A thermostat is a very cheap "repair" but if you are getting air in your system requiring it to be bled, then it is happening for a reason. It doesn’t just get air in the system. Have you done any recent work that required the cooling system to be opened up (radiator or rad hose changes, etc)? Have you ever replaced the water pump? I believe it is ran off the timing belt so if it’s leaking you might not see it until it gets really bad since it is behind the timing belt cover.

 

In any case of overheating, after making sure the coolant is full and the fan works, the next step is to just replace the thermostat rather than wonder about it. You don't need to take any hoses off to replace the thermostat. Take the two screws out and open the thermostat housing, push the cover to the side and R&R thermostat and gasket.

When bleeding, it helps to park the car facing uphill if possible so that the radiator is the highest point. At least have it on level ground, not downhill.

 

where is the thermostat... haha

 

Are we talking about a 96 Civic here?

 

yeah you actually do need to take the lower hose off because it is connected to the thermostat and it makes it a billion times easier to get down there and unbolt the thermostat.