ok ,which temp sensor did u change,i take it that it was the one for the ecu it should have a multy plug connected to it at the back of and under the inlet manifold,a pure bastard to get at i can also asume that you have checked all the leads etc etc and crank sensor gap. take out the plugs and have a good look at them they could be soaked in fuel and black sooty deposits.overfueling is normally caused by either a faulty map sensor or the ecu watertemp sensor,after that its basicly ecu related which means maybe a chip gone bananas or internal processing,
if all the sensors and other bits are ok it may be worth checking wireing of the above sensors to the ecu as there may be a bad connection at the ecu plug,sometimes pins can push back into the plug itself,you can also check running voltages at the pin connections
is this problem only at idle or does the car misfire and sputter at higher revs and normal driving?if you need pin voltages and stuff let me know