1994 Lexus ES 300 Stalling

I see from reading some of the posts on your forum that I am not alone with this problem: My 1994 Lexus ES300 starts up just fine first thing. However, it idles for a minute or two, then shuts off. As if I turned the key off. It doesn't bog down and sputter out. It just simply shuts itself off clean, and won't immediately restart. It I wait a while, it will restart, but shuts off again in a matter of seconds. What gives? Could it be an O2 sensor. I tried pulling a code manually, by jumping the E1 to the TE1 terminal on the diagnostic connector, but it gave me no reading. What gives? Thank you.