I have a 1993 240 DL sedan that runs for about an hour before it runs rough then stalls out. I replaced the MAF but still have the same problem. However, if I unplug the MAF, the car starts right up again. Any help with this issue would be greatly appreciated.

 

make sure the hot air intake flap in the airbox under the air filter isn't jammed open. thats connected to the foil 'dryer' hose that goes from the exhaust manifold cover, and its intended to give the engine warm air in very cold weather, but it often fails and sticks open, then your MAF gets really hot air and cooks itself. I just wire them closed.