About a year ago, my parents gave me ownership of our 1996 Grand Cherokee Lardeo. About a month after they gave it to me, I was taking it to go buy some electronics when the Check Engine light came on. I took it in to get it looked at, and they said something was wrong with the Catalytic (Or Catalydic, I'm not that fluent in automotive parts) Converter, so I paid to have them replace it. A week later, the 'Check Engine' light comes on again. I take it back, and now they say somethings wrong with the air filter. So now I'm ticked, if the air filter was busted, why didn't they notice when I was there a week ago? So I pay up, get a new filter, and drive away. The light stays on for three more days and goes off and stays off on the fourth day. I drive the 6-Cylinder version, and was wondering if anyone could tell me why I just had to pay over $700 in automotive repairs? I'm worried that this event could happen again, and while I don't want to fork over another $700, I don't feel like having to deal with the engine exploding...Any advice?