1991 jeep wrangler 2.5 4 cylinder that has been quiting at stops sometimes and will only restart if you turn off the ignition and wait a short time?

If it acts like it starves of fuel check the fuel pump relay. I had a 1990 wrangler which would intermittingly fail to start. Temporarily replace the fuel pump relay with the horn relay, or another one of the same size. If that solves your problem its about a $10. fix.