Hi

I'm a owner of a 1991 500SE 126. No problem starting
in the morning, however when you try starting it for
the second time it wont start. The engine is turning
but it wont start. If you leave it for about five
minutes it will start immediately. This is very
annoying when you quickly want to stop somewhere and
have to switch off the engine. If it doesn't start the
first time you have to wait 5 minutes. Any ideas?

Thanx
Danie Eloff

Fuel pump relay would be my first guess. Since you state "If it doesn't start the first time you have to wait 5 minutes" which sounds to me like it tried to start just didn't. It is firing off what little fuel pressure is left. The relay is located right of the brake booster and will have 8ZYL with an RPM limit (5900?) printed on the top of it. If you open it up you may find broken sloder joints and simply resoldering them might fix it. Once a gain just a guess.

fasthair