Saab: Intermittent no-start and occassional engine failure, model saab, vacuum leak

Question
I am having a very strange and apparently complex problem with my Saab, as I've had it dianosed at 3 Saab specific shops and nobody has an answer for me. If I drive my car for ten minutes or longer, and then turn it off - it will not will fire until the car has sat for a couple of hours - at which time it will start up strong as can be and will run fine MOST of the time. However, more and more frequently, my car is dying between intervals and it truly becoming too unreliable to drive. Also, at random points, my car will actually die as I'm going down the highway, and it has no discrimination of speed - it will happen at 5 mph and also at 70 mph. I feel unsafe in this vehicle, and unfortunately in my situation I can't trade it in or get another car. Any suggestions? The best "answer" I got was a possible cam sensor failure, or they said it may be that my fuel pump is overheating. I don't think so. My CHECK ENGINE light is comstantly illuminated and the code is for a large leak in the evap system - if that's worth anything. Thank you for your time!
~ Jeremy

Answer
Jeremy:
 You did not state the year or model SAAB you have...as my profile notes, my direct hands-on experience is for the older 900's only...1990 and older. I can, however, offer some general comments.
 First thing to check is whether the problem is due to lack of fuel or lack of spark. Several 'simple' ways to get some idea; firstly, for checking spark...tune the radio to a dead spot on the AM band and listen for background ignition noise...this will be a sort of 'spark detector' if  you can listen for slight background noise changes...not always possible, but worth a try..
 Secondly, for fuel supply matters.... could be a defective temperature sensor. Also, could be a vacuum leak, easily tested by spraying carb cleaner at various hose connections and noting any engine speed variations...if there are any, a leak is likely at the point sprayed at that caused the leak.
Since the evap leak signal is for a system that is for pollution control, NOT engine performance, I doubt that the "check engine" indication has anything to do with the problem you have with the engine.

 And finally, but MOST IMPORTANT: I suggest you subscribe to a site <alldatadiy.com> which, for $25/year will provide you on-line with the very best info on your particular car available...well worth the investment!
  Hope this helps,

               Jerry