I have '93 MBZ 300E 2.8 with 140K miles on it. The problem is if I start the engine and drive less than few minutes like to driveway wash the car then back to garage and let it sit in there for a while or over night. sometime it will develop serious vibration when start the engine but vibration will went away about 20-30 seconds later. Last week the same problem happen again but this time engine stopped and can not start again. The engine was able to start next day when I try to press the gas paddle to give more gas to engine. Engine was started but exhaust smell very bad. What is the possible problems?