BMW Repair: 92 BMW 318i warning dash light, catalitic converter, dash light

Question
HI Rahim, I have a dash light that has been on in my car since the purchase of my vehicle 2 months ago. It is a circle with dashes around it in.(it lights up red) I thought it might mean i need an oil change so i changed the oil, it stayed on. Also when I start my car after having it sit for a while the RPMs take a while to stabilize at less than 1000 RPMS. It also makes a rattling noise almost as if something has come loose int the engine or on the exhaust, but that isn't the case because after I hit the 3000 RPM line my engine then becomes smooth sounding again. I have asked Josh a similar question but I was hoping you might be able to give me some feedback as well. Basically, my questions are what does that dash light mean? and is that rattling noise related or the reason for the warning light? oh yeah and what needs to be done. thank you very much.
                          Sincerely,
                              Patrick

Answer
Hey there Patrick, If I'm not mistaking that light is your brakes light and it usually means your breaks need to be changed.  Your break pads should have a sensr with a wire on it and it is basically a magnet and when the pads get too low either in the front or the back it turns on that light as a reminder.  as far as the rattleing noise, that could be a number of things.  Most likley the catalitic converter.  or an exhaust component.  Start with that and let me know how it turn out.
Rahim.