Car stops on its own

I have a 1999 Toyota camry with 196000 miles on it and sometimes when I try to turn quickly the car stops on its own without any warning or noise. The rpm falls very low at that time.

The problem might be with the power steering pressure switch mounted on the rack and pinion assembly.

This switch sends a signal to the computer when the pressure in the power steering system increases so the computer can command the idle air control valve to increase the idle speed to compensate for the load the power steering pump imposses on the engine. If this switch isn’t working, the computer won’t command the idle air control valve to raise the engine speed, and the RPM’s slowly drops until the engine stalls.

Tester

The engine idle speed may be a little low, to begin with; so that the extra load, of more effort from the power steering pump, may be the camel that broke the straw’s back.
Have you let your tune-up stuff go: air and fuel filters, spark plugs? That could contribute to, or cause, the problem.