The problem you seem to be having is the cooling temp sensor. It controls the fan speed which has two speeds. Try that.
have the engine timing checked. if the timing is wrong the engine will overheat, are you loosing coolant?is the fan working, is the water pump working?
You need to check the operation of the radiator fan.
Possibilities: Cooling fan not working. Low on coolant. Clogged radiator, radiator hose or block.
Engine may overheat and seize
mixture of the radator fluidThis answer is possible but it is not correct and is a poor choice. There are a number of reasons why a car's engine overheats and the original question doesn't give enough information about the car and its overheating symptoms to deduce the answer to being a mixture of radiator fluid. It's not a good way to answer at all other than it being a guess.The engine can overheat b/c the radiator is old and fill with rust/dus particles that clog it up and the engine as well as the hoses. It can overheats if there's a cooling fan and it's not being turned on at lower speed (bad relay switch or fan motor). It can overheat if it's low in coolant or that the water pump is not working well. It can overheat due to a bad/broken head gasket. It can overheat with trapped air in the cooling system that needs bleeding. When driving with AC on uphill for extended period of time, it can and prob. will overheat, etc. Many reasons for the overheat and to simply give the answer of mixing radiator is simply naive and dull. Do more research being being trigger happy with the fingers :)
when overheating occurs at highway speeds the cause is usually. a radiator or coolant circulation problem, Check for a restricted or clogged radiator.
Check coolant level Cooling fan working? Dirt or clogged radiator? Defective radiator cap?
Could be debris (leaves, rodent nests, etc.) blocking the air flow through the radiator.
probably need new head gasket
check you water (coolant) level, make sure thermostat is working, radiator leaks, sensor problem
radiator plugged.or coolant low
It could be a bad fan clutch. If the fan clutch goes bad it could cause it to overheat while idling, but it would cool off when driving due to the wind going over the radiator.
Make sure the radiator fan is operating properly. You should also check your coolant your radiator might need flushed or it may need burped
A likely cause is an internally restricted radiator.
Driving slow for a long period of time on a very hot day. Or the result of another mechanical issue (such as the failure of the radiator fan or the fan belt).
Could be,Low on coolant.Cooling fan or fans not operating correctly.Coolant circulation restricted (blockage inside radiator).Sticky or stuck thermostat.Air circulation through radiator restricted (blockage outside radiator).
Low coolant? Cooling fan not working? Radiator plugged or air flow restircted? Defective radiator cap?
Clogged radiator, bad water pump, defective fan or fan thermal relay.
The cooling system has probably been compromised with radiator solder seal or radiator sealant. After the vehicle is warmed up, use your hand to carefully feel the temperature of the air flow through the radiator. It should be warm all over. If there is a cold spot, then there are plugged portions of the core. Since it only overheats periodically, the cold spot may be relatively small. If you can detect the overheating event while driving, turn the heater on full to cool it down. If this trick works, you definitely do not have sufficient radiator function.
I do not have a Grand Marquis so my engine does not overheat! Fords and Ford products tend to overheat and always have! Let's check a few things. How long has it been since you changed the thermostat and the coolant? Those two things are the most likely culprits. What is the condition of the hoses? Have those been changed in the last several years? If you have changed the hoses, the thermostat, and the coolant, and it still overheats, then it is time to take it to a radiator shop and have the radiator rodded out. ========================================================== I have been driving Ford models for over 40 years and have never had an engine overheat . Don't forget the basics , engine cooling system level etcetera . Check for a fan clutch problem , a problem with the water pump not circulating . Ford also states that if you exceed 60% antifreeze in the distilled water / antifreeze mix that it could overheat in hot weather
The radiator fan is not working,or not working properly,or possibly the thermostat is bad.But,usually if the thermostat is bad the engine would still overheat even if you speed up,so I would suggest testing the radiator cooling fans.
A leak can turn major in a hurry. If it overheats just a little too much it will ruin the engine. Have it fixed as soon as possible
Usually car that only overheat in traffic have a radiator fan that does not work. It will not over heat while driving because their is enough air flow.
Check the cooling system, and I mean everything. Thermostat, temperature sesnor(s), radiator clogs, radiator cap, badly damaged water pump, belts, you could simply need to add more antifreeze. If it isn't your coolant system, then it's your driving habbits or driving conditions, in which case you may want to slow down, get a car that can handle harsh driving, or upgrade your radiator. Also check that your electric fan is coming on.
Probably it has either run out of coolant or the cooling fan is broken. Some large engine cars in really hot weather need a larger radiator fitted so it doesnt overheat....like driving a v8 around town in the summer in Spain for instance.