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how to changing engine coolant on a 1993 mercury grand marquis gs.
Location of coolant temperature sensor on a 2003 Mercury Grand Marquis?Read more: Location_of_coolant_temperature_sensor_on_a_2003_Mercury_Grand_Marquis
A crack near or on the thermostat housing can cause a coolant leak in a 1996 Grand Marquis. The thermostat housing is located near the manifold on this vehicle.
The thread on cap on the engine coolant reservoir is the " radiator cap " on a 1995 Mercury Grand Marquis
On a 1997 Mercury Grand Marquis : The thread on cap on the engine coolant reservoir is the 16 PSI pressure cap / radiator cap
On a 1997 Mercury Grand Marquis : The thread on cap on the engine coolant reservoir is your 16 PSI pressure cap / radiator cap
I looked at motorcraft . com and looked up the 1998 Grand Marquis and it shows : Coolant Temperature Sensor Connector Motorcraft part number ( WPT 431 ) Leads : 2 - brown - male
because you have a bad head gasket and oil and coolant are getting into the combustion chamber from the passages.
You probably have a bad head gasket on your engine.
replace heater core and or themostat Coolant level may be low not allowing hot coolant to circulate properly, check coolant level.
According to the 2003 Mercury Grand Marquis Owner Guide : It came from the factory with a 50 / 50 mix of distilled water and Motorcraft Premium Gold Engine Coolant ( that's YELLOW color , meeting Ford specification WSS-M97B51-A1 )
where the starter located on a 1997 grand marquis