Car has been overheating only when I leave the car sitting for 10-15 mins. When I drive it goes back down to normal..as well as when the car is warming up I have a jumping idle, that I had thought I fixed (screwed in FITV white thing, checked all vaccum hoses, and IACV valve), that will go away if I tap the gas a couple times.

Now it's either my coolant system or thermostat...would it be one over the other? I was thinking I have air in the coolant system, which would cause the bouncing idle. A month ago, I realized I had some type of substance floating in my resoviour for my coolant, so I poured that out and filled it with water...which I'm guessing now is causing my overheating..

Just wanted to get a second opinion on if I should buy a new thermostat, get a coolant flush, or do both! Thanks for the replies!

 

I would definately look into a thermostat problem, but seriously, get some coolant in there.

 

well since it's a 2 gen.. i'm guessing it's time for both.. my friends civic had a new radiator that cooled like hell when he was driving.. needle would be below the C mark at highway speeds.. he never had heat either.. we replaced the thermostat and now it's a little below normal stock operating tempt when he's driving.. it's like $30 for a thermostat and coolant flushes are mad easy even without those gay kits.

 

Try flushing the coolant (or in your case water) first since that is cheapest replacing it with a quality coolant. Then make sure it isn't using that up indicating some kind of leak either from radiator or hoses. If it still wants to overheat, change the thermostat. Something like this happened to my last DA, but it was a slow leak that got worse, until finally my DA was drinking more bottle water (nice and cold) than I was. Will never do the water thing again, and will address the problem before it gets really bad.

 

if oyur flushing the coolant might as well change the thermo cuz you loose a bunch of coolant when you do that.. not to mention the mess.. so flush the syste and when it's drianed replace the thermo.

 

Alright cool, thanks guys!

Should I do the coolant flush throughout the entire system, or just the radiator? If it is the whole system, I will need to do a search on a how-to-do...I'm sure it can't be that difficult.

 

entire system if you can.