White smoke plume

[sammm2]

I recently started my jeep(it was already hot from a run to thr store and a large plume of white smoke came out of tail pipe. not oil. It 467 del sol ave pleasanton california only happened once. I programmed it back to 87 and mpg. Thats it. What Dodd I do wrong? I had at 91.2010 jeep 5.7 Grand jeep Cherokee