1 or 2 times a week the engine just dies?

98 Buick LeSabre.3.8 Driving up hill, down hill, coasting, it doesn't matter. 1 or 2 times a week the engine just dies. Sometimes I can catch it full throttle and it will pick up and run fine. or throw it in N on the fly and restart instantly. New fuel pump and filter Usually starts good. some times I have to stop cranking it after 5 sec 1,2,3 times before it starts. This only happens 1 time every week or two. I've been told after the engine is running you can unplug the crank sensor and it will still run. So this rules that out, Yes? Also told Cam sensors are not usually intermittent they either work or don't, Yes? It's been doing this for 1 Yr The manager at Advance auto said get a good computer diagnostic done. He changed $600 of parts on his mothers car before the computer told him there was a broken wire to a sensor. How? He says a good comp diag can send voltage through the wire to test the sensor and can tell if there is a broken wire. I haven't done that yet hoping some one could lead me in the right direction.

Thanks
David