You may want to check the sensor when it is acting up. Put one of the wires from the VOM to ground and the other to one of the 2 posts on the coolant sensor. Take the reading on both posts. They should be very close to one and other. If not, it is faulty. You may try to swap them over. (One goes to the EZL, ignition, and the other goes to the ECM for the fuel)
VOM = Volt Ohm Meter.
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