my wife was driving the car the other day, a 84' 300cd when she got home the engine wouldn't stop running after she had turned and removed the key. after a few minutes, not knowing what to do, she put the key back in. backed the car into the driveway and then moved it forward again into the garage and tried again. this time the engine turned off. i noticed the other day when i was starting the car that the key would not turn at all, i removed the key and then successfully turned it to start the engine. i have also noticed that sometimes when locking the car the passenger side door is very slow to lock (5-10seconds) or that it won't lock at all. this car is new to me, but i suspect it a vacumn related problem or a key problem? i would like to fix this problem myself and would very much appreciate the help from the forum members.