Key not in the ignition is always a favorite, failing that the wopple valve is stuck in the kranst position and therefore your dipliod is failing to crunge properly.
Avoiding the stupidity - does it turn over, is your fuel flow good, do you have a spark? If its diesel hows the compression? Really we can't help you unless you give just a teensy weensy bit more information
Seriously, I can help… or at least know the guys who can. You see I once had a problem with an engine and they fixed it over the phone!
When I called they asked for the symptoms, so I described the noise the engine made.
Simply! Was their reply, when I inquired as to what they thought, I was informed that my neutron-flux capacitor had inadvertently injected some of its bar-bar juice into the mega drive over rider system. As such that had lead to the melt down of my super megatron laser beam which would normally feed the pactor-gama injectors with fuel!!
Do you know, I was so relieved, there was me thinking it may have been something serious.
You too can have this good advice from Zob Zab Zig Marine Services by calling tel. 866301