Engine Problems Due to Distributor Cap and Rotor, Bad Ignition Wires, or Valve Cover Gasket Leaks on Mercedes-Benz 300TE

A rough running motor or lack of power can be caused by a failed distributor cap or rotor, ignition wires (or their resistors), or valve cover gasket leaks. If the valve cover gasket leaks, oil can pool where the ignition wire resistor connects to the spark plug. The resistor can fail and the spark plug may not fire because of a short circuit through the oil.