My car has been running hot for the past few weeks also. I have came to a conclusion that I still have some air in the system, and that the temp gauge sensor is bad. Sometimes the needle will bounce some. Here is what it will do, it will warm up and it will be above 176F, and it will stay there for like 15-20 minutes, then it will go up to the next notch and stay there and not get any hotter. Sometimes when I get the rpm's up high enough the temp will drop down some. A previous owner also added a switch to the Aux fan, and this sometimes helps cool down some, but still not that much...