Yes, it will still crank if the crankshaft sensor is if faulty. It will disable the
ignition system, but a press on the accelerator will not cure that. Therefore
my best bet is a vapor lock. Heres a simple movie I made about
measuring the fuel pressure to see if the regulator is faulty.
http://www.pvv.org/~syljua/merc/FuelPressureME.mov
You can do the same, and that you should look for in your case, is the last
step, if the pressure falls rapidly after you turn off the engine.
The regulator is not the only reason for this problem, it could also be caused by leaky
injectors of return valve in pump, but the first step is to see if you have a fuel pressure problem.
Ok?
br,
syljua