could be a couple of things, your o2 sensor may be on its way out (when they are hot they work the best, would explain hot starts), could be spark related, but as it does fire up, its unlikely. when you cleaned the t/b, did you happen to do the sensors at the t/b as well? they may not have been touched when you cleaned t/b. you say that re-set the
ecu worked for a few days? get your local mechanic to put his scan tool on it and see what codes are thrown up. that will be the best (and cheapest) way in the long run.
col