Trouble starting S600
 

I have a 1995 S600 coupe. After it has sat for about an hour, I have to hold the accelerator down in order to get it to start. If I do not hold the accelerator the engine will spin and hit but will not start. It will even kill the battery in this manner. Even if I hold the accelerator, it still spins for a while before it starts. I have replaced the fuel regulator, plugs, distributor caps and rotor buttons. Sometime after it starts I smell a strong smell of fuel. Does anyone have any idea what my problem may be?

I would suspect the fuel accumulator.

Try doing a search for "accumulator". There might be a lot in the archives.

s-600 hard start
 

sounds like something is leaking fuel into the engine (a lot of fuel). If it were one injector, it would still start. Look for the fuel pressure regulator and check to see if leaks fuel out the vacuum line (and into the engine manifold)

these engines should be a 'touch nothing but key' start.

s600
 

I recently replaced the fuel regulator and it still does the same thing. I hope it isn't the injectors because the cost about $300.00 each. If it sits for over 24 hours without starting, it starts immediately. Could this be because the fuel that has leaked into the cylinders has evaporated by this time?