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Crown vic keeps overheating

HELP!! I’m having a problem with my 92 crown vic overheating the radiator and thermostat have been replaced, the temp gauge never goes near the hot range but the engine gets so hot it shuts down while I’m driving. I am a rural mail carrier so I use the car for about 5 hours a day, I have to stop and let the engine cool by opening the hood for about a half hour after driving for 1 1/2 hours. I am not lossing any coolant and the fan appears to be working.

If the temperature gauge doesn’t show the car overheating, what makes you think that is the reason it is shutting down?

It is more likely you have a problem that occurs when the car gets to operating temperature. It could be something totally unrelated to the cooling system.

Who replaced the radiator and thermostat, you or a mechanic? If it was a mechanic, you need to dump him and find a technician who doesn’t just throw parts at the problem.

Thank you for your response!
the car has been to 2 mechanics already, the engine will work fine after it cools off. when I open the hood you can feel the heat coming off the engine, the coolant is very hot and several of the hoses/parts are so hot you will burn your hands. The first mechanic found the thermostat was upside down and the second found cracks in the radiator.

Laurr312 wrote:
when I open the hood you can feel the heat coming off the engine, the coolant is very hot and several of the hoses/parts are so hot you will burn your hands.

Engines run near 200 degrees. The things you list could certainly be normal.

I deleted my comment. The other comments make more sense.

Like lion9car said, if the engine is running at normal temperature, things will seem very hot under the hood. That is normal.

The coolant normally gets very hot, but the important question is: How hot is it? It should be in a certain temperature range, and one sign it is too hot is when it boils. Did you test the temperature of the coolant? Was it boiling?

It sounds to me like you either haven’t found the right mechanic or you may have given these two mechanics too much information. If you came in and said, “it’s overheating,” you may have led them astray. You need to take the car to a mechanic and say: “The car shuts down. If I let it sit a while, it will start again. Please see if you can figure out why it is doing this.”

There is a good chance something is heating up, expanding, and losing contact needed to make the car run, but it’s probably not related to the cooling system. If you have a problem with your cooling system, get the cooling system pressure tested. Otherwise, just tell them that the car dies, but will start after sitting a while, and let the mechanic figure out the reason.

You might want to check for spark when the engine shuts down. This can done by carrying an extra spark plug in the vehicle. When the engine shuts down, remove a spark plug wire from a spark plug and insert the extra spark plug into the plug wire. Lay the spark plug onto the engine and then have someone crank the engine over while watching the tip of the spark plug. There should be a bright blue spark at the tip of the spark plug. If the spark is more of a yellow color or is non-existant then there’s a problem with a component in the ignition/engine management system that’s failing when it gets hot.

Here’s a list of components that can fail when they get hot causing the engine to shut down.

Crankshaft Position Sensor.

Ignition Control Module.

Ignition Coil.

Magnetic Pickup in the distributor.

Tester

The OP is going to show up at the shop with a list for the mechanic, and the last item on it is going to be “Tester.” :slight_smile:

I’m betting on the ignition module…Overheating does not seem to be the issue…

Your comments that the engine seems hot to the touch and that’s why it is shutting off may or may not be correct. It’s hard to say if your engine is overheating or not from your description. Engines at operating their normal operating temp and the hoses too are very hot to the touch. Try it on another car that’s working. Any difference? Do you hear the coolant boiling in the radiator?

I’m assuming the coolant is a 50/50 mix, fresh, has been properly air-bled, the radiator cap is verified to be working, and the cooling system is filled to the top. And it isn’t leaking. And your mechanic has verified the normal flow amount (by visual inspection) through the radiator as the car reaches operating temp.

There’s a couple of experiments you could try beyond that.

  1. When you think the engine is overheating, pull over, pop the hood, and verify the radiator fan is spinning like a banshee. If it isn’t, that’s a problem which is easily fixable.

  2. After verifying the above, next turn the heater control valve to max (hot), and the heater fan to max, and see if the engine appears to cool down. Does it cause the guage to go down? Does this prevent the engine from shutting down?

Also, when you say the temp gauge doesn’t get near the “hot” range, do you mean it stays in the normal range it always has? On most cars the temp gauge never goes above a certain point under normal driving conditions provided the cooling system is working. Usually that point it about 1/2 way up the scale. Is your gauge going above 1/2 up the scale, and if so, is this higher than when the car was working correctly before?

WOW!! Thank you all for great info! I will check on the items and listed.

I believe this series engine is designed to shut down if it overheats so if all else is alright check for something giving the ECM an erronous signal,causing the engine to shut down-Kevin