Volvo Repair: 1991 940 turbo / Fuel Pump Relay, spark plug wires, crank shaft

Question
Hello bilbothegreat,
I have done alot of research on the subject of just stalling - I have seen alot of people out there in Volvo land w/ the same problem as I have.
My '91 940 Turbo runs great and every now and then she just dies! No sputtering/no chocking,hot,cold,fast,slow,stopped when ever- runs great for a week or so then decides to die-After a couple of minutes she will start again.
Of course I went staight to the fuel filter(replaced) drove down the street and died? No Check engine light --- is the fuel pump relay/ fuel injector  relay /radio suppression relay crank shaft sensor/ power stage... I am just getting more confused, also I am afraid to bring it in to a Volvo dealer and get my head cracked
by a bunch of stuff that I dont need - or is this problem so advanced that there is really no sure, one thing fix it could be anything or can we narrow it down to a few? Thanks, Kevin  

Answer
Hey Kev...
          Yes,these days complexity rules the auto world...including your 940 turbo.
          You may want to test your vacuum system...should be between 25 and 30in....
          Fuel pressure relays do fail...not often.
         If the f/p relay fails...it will do exactly what your car is doing...locate it and next time it stalls...hit it firmly with a screwdriver handle or something smaller....see if that helps.
            Crank angle sensors can do the same...but you can't hit it...and it's a lengthy job to replace it.
           Check your...spark plug wires and coil wire with ohm meter...easy to do....clean coil and related connections....very well.
          Lastly,get your Volvo dealers opinion...you can do the repair yourself...if you have the ability.
             I wish you luck,
                 Bye,

                   Bilbo