I have a 2001 Buick Park Avenue. What could make car cut off while driving?

Security light flashing while cranking?

Look in to your cam shaft positioning syncer I was haven the same Problem out of mine till I changed it and it runs like a champ now Good luck

Check and see if it's your mass air flow sensor.. unplug the connection to the sensor and run the car -if no stalling - then you found the problem..

I had the same problem after several hours of trouble shooting i found the problem to be the VATS system (vehicle anti theft system) the chip in the key had come loose then fallen out at a later date...no chip no start i replaced the key and also found 1 of the relays to be bad...replaced problem solved its been running well for over 3 years now...this would be a good place to start