I have a 01 Hyundai Accent GS, I have the nice loud muffler on it. Yesterday my check engine light came on(I have not idea why seemed to run ok) So I was planning to work on it on Saturday and replace the plugs, air filter, run fuel injector cleaner, and change the oil. And now since yesterday I need to do the front brakes too. So anyway driving home tonight all of a sudden the car is normally at about 2k rpms to do 65 mph now it was at about 3500 rpms and there was a noise that sounded like an exhaust leak. Once I got home I checked it doesn't seem to be coming from the exhaust more of the engine area. The exhaust manifold doesn't seem to be leaking from what I can tell, but the motor itself is running very loud, soundling like a normal hole in the exhaust sound. So my questions are does anyone have any idea what is wrong? Do you think I can chance driving it to school tomorrow and to an advanced auto to check the check engine light, and to the DMV to get new tags for my other car(About 40 miles)?