car runs 17 minutes dies will not start next day will start replaced elecrontic modular & coil pack now wont start at all

3.8L? We ran into this with a LeSabre, it did not have any trouble codes, just would die for no reason, then no start, would start with N/P in 1 to 2 hours. Fixed problem by replacing the crank sensor, it is behind harmonic balancer, follow wires down on front side of engine to find it (around crank pulley). This sensor is inexpensive and replaced easily on our car with just a couple of bolts mounting it, just make sure slots on sensor are aligned to the 2 timing discs on back side of harmonic balancer. I was told we needed to remove harmonic balancer but that was not the case for us. It is possible that during the coil pack/ignition module replacement crank sensor wires were pulled a bit and broke the already cracked sensor. Place for you to check, Hope this helps! Mike