Draining

Coolant Temperature Sensor:

Without removing radiator pressure cap and with system not under pressure, shut engine off and open draincock. The coolant reserve tank should empty first, then remove radiator pressure cap. (if not, see Testing Cooling System for leaks). To vent 2.4L engine remove the coolant temperature sensor located above water outlet housing. The 3.0/3.3/3.8L engines have an air bleed vent on the thermostat.
Removal of a sensor is required because the thermostat does not have an air vent. Sensor removal allows an air bleed for coolant to drain from the engine block.