2001 Grand Marquis Overheating

[AdmiralYoda]

If I'm reading this right you have replaced the water pump, radiator and thermostat (twice). You should have plenty of cooling capacity.

Check to see if your AC condenser is plugged up with debris or if the fins ara all mangled from road debris. It happens over the years and if it is plugged up you could be blocking airflow to the radiator.

I'd purchase a cheap infrared thermometer and double check the operating temp. A $15 sensor that is reading high might solve a lot of problems.

 

[Lubener]

If I'm reading this right you have replaced the water pump, radiator and thermostat (twice). You should have plenty of cooling capacity.

Check to see if your AC condenser is plugged up with debris or if the fins ara all mangled from road debris. It happens over the years and if it is plugged up you could be blocking airflow to the radiator.

I'd purchase a cheap infrared thermometer and double check the operating temp. A $15 sensor that is reading high might solve a lot of problems.

That (airflow) would surely cause it to overheat in city type driving. He stated it overheats at highway speeds. That usually indicates a water flow problem of some kind.

 

[Lawnman23]

I had planned on switching vehicles and buying something new, but my work situation has changed and I'm going to be making about $30,000 less per year very soon.

Sorry to hear that man. Hopefully you will find a better gig in the future.

 

[supton]

Bummer on the job change. Hopefully the fix can be found soon, it sounds like the t-stat was bad.

 

[SwampSurvivor]

Sorry to hear that man. Hopefully you will find a better gig in the future.

Bummer on the job change. Hopefully the fix can be found soon, it sounds like the t-stat was bad.

The pay cut is less than ideal, but I'm looking forward to having weekends back. just a Monday-Friday 8 to 5 type of deal. WAY below my skillset but new employer knows what I'm looking for and knows they're getting a hell of a deal with me.

I worked 80+ days straight. That's no way to live. Had to give up all of my hobbies, cancel all plans. I saw no indication that it was going to change so I had to make a change. My blood pressure was out of control - the instant I submitted notice it went right back to normal.

I was headed for a grippy sock vacation as they say ... or a stroke.

 

[Lawnman23]

The pay cut is less than ideal, but I'm looking forward to having weekends back. just a Monday-Friday 8 to 5 type of deal. WAY below my skillset but new employer knows what I'm looking for and knows they're getting a hell of a deal with me.

I worked 80+ days straight. That's no way to live. Had to give up all of my hobbies, cancel all plans. I saw no indication that it was going to change so I had to make a change. My blood pressure was out of control - the instant I submitted notice it went right back to normal.

I was headed for a grippy sock vacation as they say ... or a stroke.

Considering all that, sounds like you made a very wise decision

 

[Brian123]

When I got the car 5 years ago, I'm pretty confident I was the first person to ever change the coolant.

This is a Start!

Numerous coolant flushes and it still turns brown quickly.

The next step!

But it never had any overheating issues.

It does now!

It always seemed to run right around 200 -210 and I never heard the fan come on unless I turned on AC

Sounds like an Airflow Issue!

This year it's been worse. We had a day last week where it was 100F out and it couldn't keep up. Even with the heat on full blast, best it could do was 235. It kept going into failsafe cooling mode if I didn't have the heat on full blast. That means it was hitting 260... Even when it hit 260, the coolant wasn't boiling but I could tell it was HOT. There's 2 temp sensors - one of the gauge and one for the computer. If they're both agreeing that something hot, I'd be inclined to believe that it's not a bad sensor.

I really think you have an airflow issue, really look at the front of the AC Condensor, after that look between the AC Condensor and the radiator and see what you see. You can also do the garden hose thing in spraying water from 1 side of the radiator to the other side and vice versay!

The other thought could be, and I hope that I am wrong, with the Coolant so brown there could be something in the coolant passages of the cylinder heads. Do the simple things 1st and report back. 1 other thought, is there an air dam in the front of the car that is missing?

 

[SwampSurvivor]

This is a Start!

The next step!

It does now!

Sounds like an Airflow Issue!

I really think you have an airflow issue, really look at the front of the AC Condensor, after that look between the AC Condensor and the radiator and see what you see. You can also do the garden hose thing in spraying water from 1 side of the radiator to the other side and vice versay!

The other thought could be, and I hope that I am wrong, with the Coolant so brown there could be something in the coolant passages of the cylinder heads. Do the simple things 1st and report back. 1 other thought, is there an air dam in the front of the car that is missing?

There is an air dam that's missing. I was thinking about that possibility as well, but that went missing last month and the car was having heating issues since this spring.

I ran over a 18 wheeler tire this spring (couldn't avoid it) and deleted the air dam / valence that goes from the bumper to under the radiator setup.

If I flip on the AC to trigger the fans, it'll suck a piece of paper very tight against the condenser.

 

[Brian123]

There is an air dam that's missing.

BINGO!

I was thinking about that possibility as well, but that went missing last month and the car was having heating issues since this spring.

Good Thinking!

I ran over a 18 wheeler tire this spring (couldn't avoid it) and deleted the air dam / valence that goes from the bumper to under the radiator setup.

These things happen!

If I flip on the AC to trigger the fans, it'll suck a piece of paper very tight against the condenser.

Very Good! Your major problem is the air dam that is missing, here is what is happening, with the air dam it draws air into the radiator, and then the air goes out of the radiator and does the cooling thing and exits under the car somewhere. It probably goes under the car by the rear axle.

Here is what is happening, with no air dam, you have air that is coming through the radiator, and it is getting pushed out and that same air is going through the radiator again. It is like a circular thing; your radiator is cooling air, but the air is coming back and maybe upsetting the air that is coming into the radiator, or the air just keeps getting reheated. The air needs to come into your radiator and do its thing and then escape. My analysis might not be 100% correct, but you need to get the air dam back on there and see what happens!