Within the 2 weeks I have had decent cold AC. but this last week I started to notice AC took longer to cool. And as of past 2 days AC has went out. When I have it on it doesn't blow hot air but doesn't blow cold either. seems that when I get close to my house it starts to get colder (20-25mins) on highway. It started with the back air getting hotter, but was always the coldest. Then eventually the front went out as well. Only thing I have done with AC system is take it to a small shop where they "filled" it up. When it was "serviced" they swore it was colder but I did not notice the difference. Could it be they filled it up with too much oil?? Or what are my options if any. Did not want to take it to shop cuz I know i'll be paying for a lot of maybe unnessary work. Oh and forgot to mention I have coolant smell coming out of vents when air is on..