I have researched the threads and have the same symptoms with my '91 500 SL. Has anyone else run into this? From a cold start the car will fire but die. Then upon restart it fires fine and keeps running. I have tried just turning the key on then off prior to cranking as suggested but same result. I have new plugs new caps and rotors and new wires along with a new fuel filter. The car runs fine otherwise but this nuisance may get worse. Thanks for the help.