Date registered: Feb 2008
Vehicle: 1997 SL600 Brilliant Silver Sport with grey/dark metal interior, 234K miles
Location: Lutz, FL
Mentioned: 6 Post(s)
Quoted: 114 Post(s)
If you have a leaky injector(s), (see fuel odor), one or more of your cylinders can be full of fuel and you may be trying to compress an incompressible substance.
Pull your plugs (plus the FI pump relay in trunk) and see if the engine spins easier (it should if only because there is no compression being built) and ejects fuel. Note the condition of all plugs upon removal and look for wetness (fuel). If fuel fountains out one or two cylinders, those are the leaky injectors.
If it still won't spin with the plugs removed, then something electrical is definitely the matter.