Misfiring - Mercedes-Benz S 350 Owner's Manual

Problem
The engine will not start. You cannot hear
the starter motor working.
The engine is not running smoothly and is

misfiring.

Possible cause/consequence
The on-board voltage is too low because
the starter battery is too weak or dis-
charged.
The starter motor has overheated.
The engine electronics or a mechanical
component of the engine control unit have
been damaged.
Practical advice
Troubleshooting
Suggested solutions
Jump-start the vehicle ( page 525).
If the engine does not start despite at-
tempts to jump-start it:
Consult a qualified specialist workshop.
Allow the starter motor to cool down for
approximately two minutes.
Restart the engine.
If the engine still does not start:
Consult a qualified specialist workshop.
Only depress the accelerator pedal gen-
tly.
Have the cause rectified immediately at
a qualified specialist workshop.
Otherwise, unburnt fuel may get into the
catalytic converter and damage it.
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