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Q: I need some tips on removing the thermostat

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I nee tips on how to remove the thermostat from a 2006 mercury mariner . i pulled the Code from the computer P0128 . it told me that the thermostat was stuck open
My car has an automatic transmission.

Diagnostic Trouble Code P0128 can set due to a faulty thermostat or a problem with the engine coolant temperature sensor or the wiring associated with the sensor. Although a faulty thermostat is the most common cause of P0128 it is not the only cause for that Code to set. If the thermostat is conclusively diagnosed as faulty, on the V6 the repair procedure is: 1) Drain the cooling system; 2) Remove the air cleaner outlet pipe; 3) Disconnect the lower radiator hose from the thermostat housing; 4) Remove the 3 bolts, thermostat housing cover, O-ring seal and thermostat; 5) To install, reverse the removal procedure; and 6) Fill and bleed the cooling system.

On the 4 cylinder engine; 1) Drain the cooling system; 2) Remove the accessory drive belt; 3) Disconnect the heater hose at the thermostat housing; 4) Disconnect the lower radiator hose at the thermostat housing; 5) Remove the 3 bolts, thermostat housing and gasket; 6) To install, reverse the removal procedure; and 7) Fill and bleed the cooling system.

If you desire that the thermostat in your engine be replaced by a certified mechanic, the recommended service to request is thermostat replacement.

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