BMW Repair: intermitten cut-out, charlie charlie, fuel regulator

Question
Hi,
My 1989 325ci is cutting out, totally.  It started when I put a cleaner through the gas tank.  
I have pulled the injectors-cleaned and, as best I could checked them.  I installed a new O2 sensor, I have installed new rotor and cap, main fuel filter, fuel regulator.  Pulled the pump cleaned and checked for operation.   After all this in the fuel system I still have the same problem, maybe it's not in the fuel system but is electrical.  It starts fine, at idle, or any RPM, it will totally shut down for just a second or two.  The check engine light comes on , but I can't get it to give me a code.  It seems like the ignition system just totaly shuts down for a coule of seconds.  I have wiggled every wire to every sensor I could find, looking for a bad connection.  I love my 325 but I need it to run.  Prior to putting in the fuel system cleaner it ran good.  It has 182000 miles with no major repairs.  Does this sound electrical?  It seems like it to me now that I've changed all the fuel system parts.  If so, where can I start measuring?  I did have one problem.  The camshaft end piece that holds the rotor, lost a side ear.  I tightened the two remaining screws after putting a spot of epoxy to help hold it in place, not that it was loose, just a precaution.  Please help!!!!!
Thanks you for any suggestions
Charlie

Answer
Charlie,

 This could be several things.., but you've done excellent work so far.  Personally I think the injector cleaner in the tank and then having problems right afterward was just a coincidence.  Since I'm not there to actually see the car in person, I cannot be 100% sure though.  This is one of those nagging problems that will take some searching to find.  

 First off I would define "cutting out" is it a sputter , like the engine is starving for fuel, or is it just a dead stop.  If it's an air/fuel issue it will usually sputter and slowly die.  If it's electrical, usually it will just die, like you turned off the key.  So if it's the latter, you are right, and there is a bad ground or something like this.  I would check the crank angle sensor on the front of the engine.  It measures the harmonic balancer's speed and sends the signal to the ECU for ignition timing.  These sensors have a thick wire that doesn't like to bend, and if it is bent it will usually snap off right at the sensor.  If this sensor's wire is broken, your spark plugs will not fire.  My thoughts are the wire could be broken, but still making contact with the sensor, and every now and then the wire will become disconnected and the engine will cut-out.

 You also might have a bad ECU, that has something loose in it, or a lead from the wiring harness is intermittently making contact.

 Check over the ECU's wiring and the Crank angle sensor and we will go from there.

 Hope this helps,
 Josh