The problem with the ECT sensor is a classy one in 95's camry and older. If you connect the car to the scanner, wierd temp readings will appear. Most of the technicians, without the scanner, will miss this problem. A cheaper way to confirm this is to connect a voltimeter to the ECT sensor and check the resitance (ohms). Turn on the car let it warm and watch the ohm readings. They should decrease as the car warms up. If the readings start going up and down erratically it means that the ECT sensor is gone. This erratic readings are interpreted by the ECU like low coolant temp and creates an enriched engine condition ( to much gas ) and the car will do a warm stall. If that's the case, buy a new ECT sensor and install it. You Just remove the old one and put the new one with a bit of teflon taoe.
good luck