yes when i installed the new radiator, i left it open and left the car running and kept adding in until full.

when running for bout a good 30-40min it would idle up and down, only when in idle after a good run on the road. now and then fan would not kick in sometimes also, temp would rise up, but when moving again. temp would drop back down? some1 whispered to me that when low on rad fluid it causes this problem? and so what else should i look into?

besides the little hoses behind the TB, temp sensor. it drives fine and all besides those little problems..

and if it's burning it what does that mean??