Saturn Repair: Problems starting, crank shaft, saturn sl2

Question
I have a 92 Saturn SL2.  I just bought the car and it has been kept in good condition (only 128,000 miles).  I've trouble starting it though. Sometimes it starts just fine, particularly when it hasn't been driven in 24 hours, other times it turns over but won't start.  I got a tune-up done including changing the coil pack- that didn't work.  I had the gas filter replaced because some knowledgeable people said it sounded like it wasn't getting gas- that got it started but the next day it wouldn't start after driving it downtown chicago.  I got a knew flex pipe and a few other gasgets because a mechanic was going to do a diagnostic test but couldn't get a good read-out because there was an exhaust leak- after the new pipe the problem continues.  I took it back to get the diagnostic test and the mechanic determined that I needed a knew crank shaft.  He put one on and it started for him.  After driving a mile away and letting the car sit for an hour and a half, it will not start.  What could be the problem?  The mechanic says two of the fuel injectors are new so the injectors are not the problem.  Also people who I brought the car from did regular maintenance on it; things like 6 oil changes a year, new alternator, rotors, etc, etc.  What should I do next?

Answer
Angie,
 First off, I would find a new mechanic.  Anybody can throw parts at a vehicle and say, "I think that will fix it." We call those guys "shadetree" mechanics.  Anyway, take your vehicle to a TRAINED technician and have them test the fuel pressure and retrieve any Diagnostic Trouble Codes that are stored in the PCM.  This will help me to better diagnose your problem.  After you do that, get back in touch with me and let me know the results.  

Chris