I brought my car in for a tune up and when it came back it seemed to be ideling low but after the car warmed up it drove fine. Then a week later when I would slow down it would either stall or not speed up when I pushed on the gas. I brought it back and they said it was the mass air meter. Then I was driving the next day on a long trip and the car was making a loud "muffler" noise and I brought it to a muffler place on the road and they said the whole muffler was cracked and put in a new one. Minutes later the same no power after slowing down problem happened again (which was supposed to be fixed two days ago with the mass air meter replacement). There has not been any smoke or bad odors coming from the car, and when the loss of power or stalling happens (which is not all the time) when I shut off the car and turn it back on it works again fine. I am obviously not a car person, but over $500 in two days and there is still a probelm, I was hoping for some un baised advice before I brought it back the the shop.Any ideas????