On my '93 LX 2.3 the temp went up while I was idling at a gas station. By up I mean about 3/4 the way up the gauge. Well the electric fan did not kick on and I am pretty sure that it should have. What engages the fan, is it the sensor on the heater core hoses or the one in the block? Where is the relay for the fan? I checked my fuses and the're good. Anyone have the same issue? Any insight is appreciated!