Problems with my Mercedes...!!!?

Hey.. I have a 1997 mercedez benz e420 with 90000 miles on it. I was driving and suddenly the car started to shake at idle at around 500 rpm .. the rpm slightly flactuatedsat idle and check engine light came on.... indicating check electronic, I kept on diving to just make it home and as soon as I got home, The care started to smell like sulfur... burned... !!!! PLease Advice