My car completely shuts off if I brake suddenly or make a sharp turn, it started acting up after I got an alignment, but no shop can figure it out and of course it only does it when I drive it. Sometimes when it shuts off it'll take 20 minutes to crank back up.
Shuts off on 1990 Pontiac Grand Am
Most likely it is a defective (1) Ignition Module or (2) Crank sensor. I used to work at a GM Dealership and this is somewhat common. have a good Diagnostic Shop check it out, NOT a tire place.
Mines a 93 and had this issue when I first bought it, a fuel treatment when I fill up always fixes it for me.