Generally the one wire temp sensor operates the temp gauge and the two wire sensor feeds the ECM information needed to make the engine run its best.
Check coolant level Could be thermostat opening and closing due to engine coolant temperature flutuation
A few of the reasons: 1. So that the coolant does not leak out of the system. 2. So that the coolant can be made to circulate through the pipes (pressure is required). 3. So that Pressure can build up in the cooling system. This allows the coolant to reach a higher temperature before boiling. Once at its boiling point, the temperature will not rise, and additional cooling is inhibited.
Yes. Water boils at 212 degrees. A 50/50 mix of water and antifreeze boils at 223 degrees. The temperature of the coolant can sometimes reach 250 to 275 F (121 to 135 C). Even with ethylene glycol added, these temperatures would boil the coolant, so something additional must be done to raise its boiling point. The cooling system uses pressure to further raise the boiling point of the coolant. Just as the boiling temperature of water is higher in a pressure cooker, the boiling temperature of coolant is higher if you pressurize the system. Most cars have a pressure limit of 14 to 15 pounds per square inch (psi), which raises the boiling point another 45 F (25 C) so the coolant can withstand the high temperatures. Antifreeze also contains additives to resist corrosion.
It is important to limit the fuel temperature so that the sheath (zircaloy) of the fuel rod is not damaged which would allow radioactivity to leak into the coolant.
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Follow the upper radiator hose to the thermostat housing. The coolant temperature sensor for the ECU (2-pin connector) is on the driver's side. The temperature sender for the guage (1-pin connector. is on the opposite side.
To the right of the Coolant temperature sensor. It has 1 wire connector
coolant temperature sensor are located where the coolant runs in the block near the thermostat housing normally the connector are on top of the sensor and the sensor itself screws in with a deep socket. The temperature sensor is usaully located where the coolant runs OUT of the engine close to thermostat housing.
the coolant temperature sensor is faulty. It will need to be replaced
it is on the back of theengine with four wires coming out the connector is blue
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
For the 2.7l v6 engine, it is right on top of the engine next to the coolant bleed valve. As you are standing in front of the car after raising the hood, look right to the left of the intake manifold. There you will see the coolant temperature sensor and connector and the coolant bleed valve, both in the same plastic housing.
disconnect the wire connector, then find the right size wrench or socket and unscrew it.
Unplug electric connector. Sensor is in water jacket so you will need to catch coolant after removing sensor. Properly dispose of old coolant. Install new sensor and just make a little snug (with open-end wrench)- do NOT over tighten. Install electric connector and top off coolant.
You should see a two-wire connector just to the right and underneath the coolant cap on the passenger side of the engine. That is the coolant temperature sensor. NOTE: look for the cap on the engine, not the one on the radiator.
It is in aluminum housing connected to upper radiator hose.Follow hose from radiator to where it is connected. The Temp. sensor is the one with one single wire connector. Other oine tells engine computer the coolant temp. and has a black moulded connector.
There are two coolant temperature senders on the vehicle. They are mounted on the head and on the thermostat housing next to each other in front of the #1 cylinder fuel injector. They are easily observable from the passenger side of the engine compartment. The one toward the front of the motor ( with brown wire connector ) is the temperature sender for the temperature guage. The one behind it ( blue wire connector ) is the one for the motronic control unit ( ecm ).