idle issues and now overheating issues

[jc27]

My 2000 civic dx hatchback is driving me crazy. I'm having idle issues and i cleaned the throttle body and checked for vacuum leak and came to the conclusion that it is the idle air control valve. So I'm going to change it. But I was driving my car and when I pulled over it started to over heat. Let me explain a bit of my previous problems. The car would overheat tons of time. Got my head rebuilt and changed thermostat. Car has been driving fine for about a month with my new head. Could it be over heating due to the loss of coolant every time you take off the throttle body? The little container doesn't look like it lost much coolant

 

[Wreckless Hype]

By little container, do you meant the overflow tank? If your car is losing coolant, you need to fill it through the radiator. You can lose some coolant when you disconnect the hoses from the TB assembly (IACV and FITV included). If you're not refilling it, air pockets in the system will throw off your cooling system. If your car is substantially low on coolant and you've only removed the TB assembly once or twice, then I doubt you lost all the coolant from there, and you may have other issues.

If your system hasn't been flushed in a while, get that done also. You can usually CLEAN an IACV before replacing having to replace it. Also, was the thermostat you used OEM Honda? I've never had any luck with autopart store brands in Hondas.

What kind of idle issue is it having? Idle low, idle high, fluctuating? Does it only do it when it's cold, or also when it's warmed up? Any check engine lights? Can you even it out by putting your fingers over the holes for the IACV and FITV?