Crank shaft position sensor and ignition control module are the most common causes for what you are experiencing, but it could also be the camshaft sensor. Although, if that was the problem I would expect a P0341 code. Are you scanning for diagnostic trouble codes? A bad cam sensor can cause the engine to stumble and stall, but will not prevent starting up again. You can test it with a multi meter.
Jack the front right corner up and remove the wheel and fender liner in order to access the harmonic balancer. Using a piercing probe on the positive lead of the multi meter pierce the insulation on the wire marked "J" on the electrical connector going to the ignition control module. This should be the second wire to the left of the bolt in the center of the connector. Set the meter to DCV and touch the negative lead to a good ground. DISCONNECT THE ELECTRICAL LEADS TO ALL 6 INJECTORS. Use a ratchet wrench extensions and the correct socket to turn the crank pulley clock wise (you need a helper to do this) while observing the multi meter. The meter should read 5 to 7 volts at all times, except once in every two revolutions of the the engine the reading will drop to zero. This happens when the interrupter on the cam passes the cam sensor. You need to observe two revolutions since the cam shaft turns one revolution for every two revolutions of the crank shaft.
Do not use the starter to turn the engine over.
If your readings are not consistent with this you have a bad cam sensor or the interrupter has fallen off the cam gear.
2001 Bonneville SSEi (retired at 365,000 Kms.)
2014 Jeep Grand Cherokee Overland (yes, I know its not a GM)