I got a 1992 318IS about two weeks ago, It's black, looks exactly like an M3, has 79,000 miles, and got it for $5,800. The guy who I bought it from told me he changed the three belts, sparkplugs, and the AC Compressor. He also said that the guy before him did the radiator. My problem is that when I was driving the car and it was in fourth gear, my shifter started to shake, i started to lose power, and the car was making a funny noise. The car was still moving but no matter how much i pushed on the gas, it still would not go any faster. I took it to a shop and got charged $82. Five minutes after I drove the car out of the shop, it started to do it again. My battery and my alternator are fine. I have no idea what's wrong, so if you have any suggestions, please, let me know.