lately the inside of my car is hot. hotter than normal, especially the center console. it feels like there's hot air or heat coming from there. i have to add coolant every 3000 miles or so. i check the oil everyday and no milky oil. the other day i had some fun getting onto the freeway and immeadiately after that my car sounds like ***. there's a rattling noise when taking off and slowing down and sounds like it's kinda choking. could it be the cat or did i screw something else.