1997 Mercury Grand Marquis V8 temperature sensor

JAHLOVEJILL

MEMBER
1997 MERCURY MARQUIS

Bob and Ken,
Wonderful site! I have a Mercury Grand Marquis that is wildly overheating. One minute it's cool as as cucumber next minute it's high in the red. There seem to be no pattern and it usually only lasts for less than 5 seconds. Today I drove it around the block from sitting overnight and the temperature gauge totally maxed out but felt cool to the touch. No leaking or smelling of any fluids. No performance problems. Yet a panic attack on wheels for me right now. I think it could be a problem with the gauge or temperature sensor. Where is that located on my car and how do I replace it?
Thanks for your time.

1 Reply

WADEP

MEMBER
3 POSTS

Here's a few things I would check. I would make sure there's sufficient coolant in the reservoir. I would check to make sure the radiator fan is working. Could also be the temperature sensor for the coolant. You can unplug the sensor and use a resistance test to verify it works properly. It should start at a certain resistance level and continue to change - steadily - until the engine has reached its prime temperature level - at this point the radiator fan should be on to maintain that temperature level and the resistance reading should plateau. Good luck!