84 Eldorado....please help

Hey guys, my neighbor has a 84 Eldorado with the 4.1 DFI motor and has a problem that we are trying to figure out. Yesterday he started the car and backed it out of the garage to get his mower out. Anyway he put the car back in the garage and for some reason he always revs the hell out of it before he turns it off (told hime to stop doing this). Since he turned it off last, the car wont start. Its cranking and cranking but it wont start. If anyone here could tell me what may possibly be wrong I would appreciate it. Thanks. By the way the car has only 37k orig miles, its a real creampuff, looks like brand new from any angle.

Does it have gas?Pulling it in and out of the garage and reving it like that makes that specific engine drink gas like it water on a 95 degree day.It may have run out of gas and he didnt notice.

Knowing the propensity of the digital electronic display to loose its fuel data when parked for extended periods of time, it wouldn't surprise me if the tank is empty. There are some more serious potentials:

1.) A broken timing chain. This happened on my father's '84 at 49,000 miles - - the car just quietly quit running while driving down the highway.

2.) A failed crankshaft. This happened on my '84 Biarritz Convertible at 49,000 miles - - my dealer's explanation was that the factory allowed a batch of poor crankshafts to get through quality control in '84 and they basically can disintegrate with no warning - - I was driving on Interstate 270 just outside of St. Louis. The failure was accompanied by an audible bang - - this could have been disguised by revving the motor.

In both of the cases above, the starter would turn the motor over - - but it would never start.

Kevin