One thing you can be sure of in this case is that it isn't the overvoltage protection relay. The OVP relay powers the idle motor and the fuel management ECU. The KE-Jet system doesn't need electronic control once warm. It does a very good limp home without electronic control. While the loss of fuel control or idle motor can cause an idling car to stall, it will not keep a warm car from starting if you step on the gas.
A 300E that dies at anything but idle and won't restart is probably suffering from a bad fuel pump relay, crank sensor, ignition coil, fuel pump, or ignition rotor/dist cap.
One other unusual problem I have seen is the fuel pressure regulator sticking flooding the motor. And of course it could be something else (bg).
Owner 24 bay BSC
Bosch Master, ASE master L1
26 years MB technician
[This message has been edited by Webmaster (edited 03-14-2000).]